Traductor. Translator.

lunes, 15 de diciembre de 2014

Desplegables y ventanas emergentes en Exel

En esta última práctica de Excel, he aprendido a hacer desplegables y ventanas emergentes.

Primero os enseñaré cómo hacer un desplegable.

1) Seleccionamos la columna que aparecerá en nuestro desplegable.



2)Nombramos la columna. 
Para ello, en la parte superior izquierda, en el nombre de la casilla, escribimos el nombre que deseamos darle a la columna. Cuando lo hayamos escrito, que debe estar todo junto, pulsamos "Enter".




3) Pulsamos en la casilla en la que deseamos hacer el deplegable. Un vez allí, clicamos en la pestaña datos y en validación de datos.




4) Cuando hemos pinchado en Validación de datos, en la pestaña Configuración, permitimos "lista", omitimos los blancos, hacemos click en "Celda con lista desplegable", escribimos el nombre de la columna con un = delante y pulsamos "Aceptar".




5) Comprobamos que el desplegable está bien hecho y tiene los componentes que deseábamos y listo. 



Ahora vamos a aprender cómo hacer una ventana emergente.

1) Pinchamos en la casilla que deseamos que cuando se rellene aparezca la ventana emergente.
En este caso vamos a hacer una ventana que nos avise de que se ha superado el presupuesto establecido, por lo tanto haremos la ventana en la casilla en la que irá escrita la cantidad.



2) Volveremos a usar la Validación de datos, y rellenaremos los datos tal y como están en la imagen.

En el hueco "Mínimo" escribiremos el nombre de la casilla que llevará la cifra presupuestal.


3) En la pestaña "Mensaje de error" escribiremos el mensaje que deseamos que aparezca cuando se supere el presupuesto y pulsamos aceptar.




4) Por lo tanto, si nuestro presupuesto es de 500€ y el precio total son 390 €, no aparecerá ningún mensaje emergente; sin embargo, si nuestro presupuesto es de 200€ y el precio total es de 390€...



*Nota: La ventana aparecerá automáticamente al superarse el presupuesto sin necesidad de tocar ningún botón.



Para cualquier duda, deja tu comentario.


 ¡Feliz Navidad y próspero año nuevo!

lunes, 24 de noviembre de 2014

Macros

Hoy os voy a enseñar cómo crear una macro. Una macro es una serie de instrucciones que tú mismo le ordenas al ordenador para realizar una función.
Empezaremos por la macro borrar.

A)Insertamos la forma que actuará como botón.



B) En la pestaña vista, seleccionamos "Macros", y a continuación, grabar macro.



C) Nombramos la macro. Nos aseguramos de no repetir el nombre en el mismo libro. En caso de que tengamos varias macros para la misma función, podemos nombrarlas como "borrar1", "borrar2".



D) Pulsamos aceptar y nos aseguramos de que está en modo grabación.




E) Seleccionamos aquello que deseamos borrar.



F) Pulsamos la tecla "suprimir" del teclado y a continuación detenemos la grabación haciendo click en el cuadrado azul de la parte inferior izquierda.



G) Con el botón derecho, hacemos click sobre la imagen que deseamos que sea el botón y pulsamos a "Asignar macro".


H) Seleccionamos la macro y pulsamos aceptar.



Por último, comprobaremos que funciona.


Continuamos con la macro imprimir.

A) Como antes, seleccionamos la imagen que queremos que actúe como botón y en la pestaña "Vista" pulsamos en "Grabar macro".

B)Nombramos la macro y de damos a aceptar.


C)En el botón de Office, arriba a la izquierda, buscamos "Imprimir" y pinchamos en "Vista preliminar".



D) Una vez que hemos pinchado en vista preliminar, podemos ver el aspecto que tendrá nuestro documento a la hora de imprimirlo.



E) Cerramos la vista preliminar, detenemos la macro y la asignamos al botón imprimir al igual que hemos hecho con el de borrar.


Para ocultar los botones a la hora de imprimir nuestra hoja hacemos lo siguiente:

A)Click con el botón derecho encima de la imagen y seleccionamos "Tamaño y propiedades".


B)Después hacemos click en propiedades, quitamos la selección del cuadro "Imprimir objeto" y le damos a cerrar.



Para concluir, debemos guardar nuestro libro de una manera especial. A la hora de "Guardar como" debemos seleccionar "Libro de Excel habilitado para macros".





domingo, 23 de noviembre de 2014

Resolución y representación de ecuaciones

Durante las últimas semanas hemos estado haciendo una práctica en Excel sobre resolución y representación de ecuaciones. El trabajo consta de cinco hojas: la portada, la fórmula de la ecuación de primer grado, la gráfica de la ecuación de primer grado, la fórmula de la ecuación de segundo grado y la gráfica de la ecuación de segundo grado.

1)Portada:

La portada incluye una serie de botones que nos permitirán navegar por el resto del libro. Los botones son muy sencillos, lo único que hay que hacer es asignar hipervínculos de la siguiente manera:

a)Hacemos click en la imagen que deseamos que sea nuestro botón con el botón derecho del ratón y seleccionamos "Hipervínculo...".


b) Nos aseguramos de seleccionar la pestaña "Lugar de este documento". Una vez seleccionada, elegimos la hoja a la que nos vamos a dirigir cuando pulsemos el botón, en este caso será 'Ecuaciones de primer grado'. Hecho esto, aceptamos y repetimos el proceso con cada botón que deseamos crear.



2)Ecuaciones de primer grado:

Al añadir la fórmula =SI(B8=0;"No hay solución";-E8/B8) , conseguimos resolver todo tipo de ecuaciones de primer grado.



3) Gráfica de ecuaciones de primer grado:


a)Creamos una tabla de valores, la "x" será un número elegido por nosotros, y la "y" se obtendrá añadiendo la siguiente fórmula: =SI(A7="";"";(A7*$E$2+$H$2)) .


b) Para crear un gráfico, pinchamos en la pestaña 'Insertar' y después en "línea". Una vez ahí, seguimos las instrucciones indicadas por el programa.


c) Por último, para insertar rótulos y títulos a la gráfica, observamos la siguiente imagen:


El resultado, al ser una ecuación del primer grado, es una recta: 


4)Ecuaciones de segundo grado:

Esta hoja es la más laboriosa de todas puesto que es necesario introducir fórmulas bastante complejas. 

a) La primera fórmula que vamos a escribir nos va servir para describir el tipo de ecuación que se nos presenta dependiendo de los coeficientes que hayamos introducido. La fórmula es la siguiente: 
=SI(B11=0;SI(E11=0;SI(H11=0;"No existen coeficientes de ecuación";"Ecuación incompatible");"Ecuación de grado 1");SI(E11^2-4*B11*H11>=0;"Ecuación de grado 2:"; "Solución imaginaria")) 



b) La segunda fórmula sirve para el primer resultado de la ecuación. Ya que las ecuaciones de segundo grado tienen dos soluciones, necesitamos dos fórmulas distintas, una para cada una. La fórmula es esta: 
=SI(B14="Ecuación de grado 2:";(-E11+RAIZ((E11^2)-4*(B11)*(H11)))/2*B11;"")



c) La tercera fórmula corresponde con el segundo resultado de la ecuación. Para obtener dicho resultado escribiremos a continuación la fórmula: =SI(B14="Ecuación de grado 2:";(-E11-RAIZ((E11^2)-4*(B11)*(H11)))/2*B11;"") 



Al introducir los coeficientes, el resultado final sería este:



5) Gráfica de ecuaciones de segundo grado:

El método para hacer la gráfica es el mismo que con las de primer grado, pero en este caso al ser de segundo grado obtendremos una parábola en vez de una recta.



Espero que os haya sido de ayuda. Para cualquier duda, deja tu comentario abajo e intentaré resolverla de la mejor forma posible. 
Un saludo y buena semana.

jueves, 30 de octubre de 2014

Factura en Excel

Durante este mes hemos estado realizando cierta serie de prácticas en Excel. Aquí os dejo la más costosa de hacer hasta la fecha.

Hoja 1:

Un menú de inicio con unos botones que nos permitirán navegar por el resto del libro.



Hoja 2:

Una tabla con un listado de la información de los clientes.



Hoja 3:

Un listado con el código de cada artículo, los productos a vender, el precio unitario, el precio de diez unidades y el precio por cien unidades.



Hoja 4:

La factura de la compra. Al introducir el código del producto y el número de unidades se autocompletará, al igual que con el código del cliente. 
Además, hemos creado dos macros:
a) Macro borrar: es un botón que al pulsarlo automáticamente se elimina toda la información de la tabla sin necesidad de borrarla manualmente.
b) Macro imprimir: al pulsar este botón aparecerá la vista previa de la factura momentos antes de ser imprimida. A continuación, solo habrá que pinchar al botón con el dibujo de la impresora que aparece en pantalla y la factura pasará a papel sin necesidad de modificar nada.





miércoles, 8 de octubre de 2014

Sociedades de la información y el conocimiento

Aquí os dejo el primer trabajo que hemos hecho en el curso sobre las sociedades de la información y el conocimiento.
Here I upload the firts work that we've done about the information and knowledge society.

http://www.slideshare.net/LidiaJEIT/1tic-navarrodel-castillolidiasociedad-de-la-informacin-y-el-conocimiento-1

lunes, 6 de octubre de 2014

El Internet de las cosas

Básicamente, se trata de que todas las cosas del mundo estén conectadas a Internet. Hoy en día tenemos smartphones, tablet, ordenadores portátiles, dispositivos multimedia en el salón, e incluso las propias televisiones que se conectan a Internet. A esto habría que añadir las videoconsolas, e incluso los coches. Sin embargo, eso no es nada en realidad si pensamos en la gran cantidad de cosas que hay en el mundo. No solo los dispositivos electrónicos pueden conectarse a Internet.
El Internet de las cosas va mucho más allá. Algunos ejemplos de cosas conectadas a la red que podrían considerarse como parte de ese Internet de las cosas serían los electrodomésticos que están conectados. Ya existen frigoríficos, hornos y lavadoras que pueden ser controladas desde un smartphone gracias a la conexión a Internet con la que cuentan. Ese es solo el primer paso de lo que está por llegar. Tanto a nivel doméstico como a nivel profesional, el Internet de las cosas podría cambiar el mundo tal y como lo conocemos hoy. Pensemos solo en algunas de las aplicaciones que podrían llegar a tener lugar. Un agricultor debe conocer en todo momento las condiciones del campo en el que está cultivando. Su trabajo consistiría en comprobar regularmente la temperatura y humedad del campo y registrar estos datos en un ordenador. Pero supongamos que todos esos datos fueran monitorizados de manera automática y registrado en un servicio online, de manera que el agricultor tuviera en todo el momento el conocimiento de cómo está el campo de cultivo e incluso pudiera conocer cómo está en tiempo real. Y todavía hay más, con sensores lo suficientemente baratos, podría llegar a monitorizar absolutamente todas las plantas que están cultivando, conociendo cómo crecen y si están teniendo problemas algunas de ellas.

Sus aplicaciones domésticas podrían ser igual de importantes. Por ejemplo, podríamos disponer de sensores y controladores en diversos elementos de una casa. Seguro que nos ha ocurrido irnos de viaje y no estar seguros de si hemos quitado el fuego de la cocina, o si las persianas, ventanas o luces se han quedado tal y como queríamos. Todo sería tan sencillo como acceder al servicio con el que controlamos nuestra casa, y no solo comprobar que todo está de manera correcta, sino incluso modificar el estado de los mismos. O si por el contrario, vamos a volver en pocas horas a casa, podemos incluso programar cuándo queremos que comience a prepararse la comida. Cosas como regular la temperatura del hogar cuando estemos nosotros allí o encender las luces de manera automática, podrían ser hechos cotidianos de la vida. Es el Internet de las cosas, las cosas que nos rodean, que pasarían a estar permanentemente conectadas.

viernes, 19 de septiembre de 2014

¡HOLA DE NUEVO! / HELLO AGAIN!

¡Hola a todos!

Ya he vuelto de vacaciones y toca ponerse las pilas otra vez para sacar bachillerato adelante. Al igual que el curso pasado, iré subiendo aquí todos los trabajos que vaya realizando. Espero que os sean igual de útiles que creo que me serán a mí.
¡Nos leemos!



Hello everybody!

I've come back from holidays and I have to study hard again to pass. At same last year, I'll uploading here all the works that I'll doing. I hope you find them as useful as I think they'll be for me.

jueves, 12 de junio de 2014

How to dissapear online

We are going to know how to dissapear following the next steps:


  • Step one:
 Desactivate primary accounts.


  • Step two:
Search for yourself on the net.


  • Step three:
Falsify undeletable accounts.


  • Step four:
Unsubscribe from mailing list.


  • Step five:
Deleate search engine results.

  • Step six:
Contact webmasters.

  • Step seven:
Consider data clearinghouses.

  • Step eight:
Check in with your phone company.

  • Step nine:
Delete your email.

lunes, 19 de mayo de 2014

Video pad

We're going to finish our term doing a video about news using a program of free software called Video pad.

What Is VideoPad?


VideoPad is editing software that helps in the enhancement of videos to give them a professional touch. It has many tools that can help you transform your homemade videos and share them with friends and family through various media. Here are some of the features of this software:

Effects

The effects in this software allow you to select from an array of fading transitions, preview them as real time applications and also set the time of the chosen effect. Therefore, you get to choose the manner in which the effects take place, control the amount of time for the effects, and preview them like they were final products.

Optimization

With VideoPad, you can easily add digital images and pictures, while also adjusting the brightness and contrast for your video. You can create effects similar to those found in old images and videos by applying the black and white effects. You can also play around with the sepia and negative toned effects. VideoPad allows you to input text or captions onto the video as well. There is also a set of great audio tools to experiment with.

Audio Tools

You can import set musical tracks or be more creative and come up with your own by combining two or more tracks. This tool also allows you to select or make your own soundtrack for your video. You can even input your own words into a narration on the video or if you have an existing one, you can simply import that to be added to the final product.

jueves, 15 de mayo de 2014

Social networks

My partner and me did a presentation about what is a Social network, how you can use it, types and security.
Here I put the link because we did it in Prezi, but, if you have problems to see it, also I write here the information.
I hope you like it!

http://prezi.com/k_zkfeul2zj5/social-networks/


A. Definition:

Alternatively referred to as a virtual community or profile site, a social network is a web site on the Internet that brings people together in a central location to talk, share ideas, share interests, make new friends, etc.

B. Before & now:

This type of collaboration and sharing of data is often referred to as social media. Unlike traditional media that is often created by no more than 10 people, social media sites contain content that has been created by hundreds or even millions of different people. Below is a small list of some of the biggest social networks used today.

C. Six Major Social Network Categories:

1.Social connections
2.Multimedia sharing
3.Professional
4.Informational
5.Educational
6.Hobbies

1.Social connections

Keeping in touch with friends and family members is one of the greatest benefits of social networking. Here is a list of the most widely-used websites for building social connections online.

• Facebook: Arguably the most popular social media utility, Facebook provides a way for users to build connections and share information with people and organizations they choose to interact with online.



• Twitter: Share your thoughts and keep up with others via this real-time information network.

• Google +: This relatively new entrant to the social connection marketplace is designed to allow users to build circles of contacts that they are able to interact with and that is integrated with other Google products.





• MySpace: Though it initially began as a general social media site, MySpace has evolved to focus on social entertainment, providing a venue for social connections related to movies, music games and more.



• Tuenti: is a Spanish social network that is similar to Facebook.


2.Multimedia sharing

Social networking makes it easy to share video and photography content online. Here are some of the most popular sites for multimedia sharing.

YouTube
Flickr
Picasa
Instagram
Vine

3. Professional & 4. Informational

3.Profesional
Professional social networks are designed to provide opportunities for career-related growth. Some of these types of networks provide a general forum for professionals to connect, while others are focused on specific occupations or interests. A few examples of professional social networks are listed below.
 LinkedIn
 Nurse Connect

4.Informational
Informational communities are made up of people seeking answers to everyday problems. For example, when you are thinking about starting a home improvement project or want to learn how to go green at home, you may perform a web search and discover countless blogs, websites, and forums filled with people who are looking for the same kind of information. A few examples include:
Super Green Me: HGTV 
DiscussionForums: Do-It-Yourself Community.

5.Educational &  6.Hobbies

5.Educational
Educational networks are where many students go in order to collaborate with other students on academic projects, to conduct research for school, or to interact with professors and teachers via blogs and classroom forums. Educational social networks are becoming extremely popular within the educational system today. Some examples of such educational social networks are listed below.
The Student Room, The Math Forum, ePALS School Blog, Classroom 2.0, Academia.edu

6.Hobbies
One of the most popular reasons many people use the Internet is to conduct research on their favorite projects or topics of interest related to personal hobbies. When people find a website based on their favorite hobby, they discover a whole community of people from around the world who share the same passion for those interests. This is what lies at the heart of what makes social networks work, and this is why social networks that are focused on hobbies are some of the most popular. A few examples of hobby-focused social networking sites include: Oh My Bloom, My Place at Scrapbook.com,
 Sport Shouting 

D. Build Connections with Caution

These are just a few examples of the many opportunities to engage in dialog via social media websites. The fact that there are so many ways to connect with like-minded individuals online can be very exciting and beneficial, but it's essential to proceed with caution. Keep in mind that not everyone who shows up on a social media website is who he or she claims to be. Exercise caution and closely guard your personal information any time you engage in social networking activities regardless of what kind of social utility you are using.


miércoles, 30 de abril de 2014

Prezi

What is Prezi?prezi logo

Prezi is a presentation tool that can be used as an alternative to traditional slide making programs such as PowerPoint. Instead of slides, Prezi makes use of one large canvas that allows you to pan and zoom to various parts of the canvas and emphasize the ideas presented there. Prezi supports the use of text, images, and videos and also provides a collection of templates to choose from to help new users get accustomed to the interface.

Prezi offers educational licenses for students and teachers. This allows students and teachers to create private presentations that cannot be access by the public.

martes, 22 de abril de 2014

Computing Security

1. INFORMATION SECURITY

1.1 . Computer Security

• Physical security . Is understood as the set of measures and protocols for
control physical access to an item. Applied to computer security as
are measures to prevent unauthorized persons from reaching
specific device or terminal .
• Logical security . There are different protocols , algorithms and programs
can directly manipulate information by controlling access to the same
you from third parties. Passwords are encrypted and codes are part of the
logical security .
• Human Security . It is that which resides in the user who runs the
information. It is the responsibility it takes for the information and
measures and protocols of behavior held to manage
properly . Choosing strong passwords, non-disclosure and key
use of security tools are human security.

1.2 . Data protection by encryption

● ENCRYPTION .
Message encryption is certainly one of the
older systems to protect
communications. Different systems
coding, have evolved over the
history , but has been the application of machinery and
when computers cryptography algorithms
have achieved true complexity .
Symmetric encryption . Use the same key to
encrypt and decrypt . The key is shared by the
sender and the receiver of the message , using it the
to encrypt the message first and the second
to decode .
Asymmetric encryption . It uses two different keys, one to encrypt and one to decrypt . the
shared key to encrypt and public , the decryption key is secret and private . the
sender uses the recipient's public key to encrypt the message and , upon receipt , the
receiver uses its private key to decrypt it. This type of cryptography is
also called public key .
● HASH FUNCTIONS
The functions , are called cryptographic reduction , you have irreversible.
These functions operate on the data obtained from them a key that represents
nearly uniquely . The fundamental property of these algorithms is that if two
hash keys are different , it means that the data that generated these keys are
different .
● steganography
It is a set of methods and techniques to hide
messages or within other objects , so that not
perceives the existence of the former. A hidden message
formed by the first letter of each sentence in a text is
a form of steganography. There are programs that
enter data into images or music files
taking advantage of the limitations of the human senses ,
well as inaudible frequencies in a file
audio or small "imperfections" in an image.

1.3 . Securing Communications :

● THE FIREWALL
A firewall is a
element responsible for controlling and
filter connections to a network
machine or set of machines.
It is a basic mechanism
Threat prevention
intrusion. It involves
barrier between
computer or private network and the world
outside. Controls access by
entrance and exit to the outside , filter
communications, records
events and generates alarms.
● PROXY SERVERS
It is a computer that acts as an intermediary between a client and a destination. when a
customer wants information , connects to the proxy server rather than with the
target server.
The proxy server contacts the server
destination as if the customer
and once the information is obtained
sent to the computer that initiated the request.
In a local network for a proxy server can
offer this service to all computers,
so that communications are not
performed with the outside but only
with the proxy server. Furthermore, this
is the only server that accesses and
exchanging data with the external network.

1.4 . Security Wi- Fi network

When the information travels over radio waves , they are accessible to any
receiver is within the area they cover, is authorized or not.
With the proliferation of such networks is quite common to find that the same
terminal receives signals from several neighboring networks. It is therefore important to protect
Wi -Fi communications possible
intruders.
There are two reasons for this. first
place to ensure the confidentiality of
communications network . Secondly ,
to prevent an intruder from using the
network to carry out illegal actions
will end up being charged to the owner of the
same .
To protect Wi-Fi networks used various
security protocols the most common
are : WEP , WPA and WPA2 , provided that
it may have been in use since the latter
which is the safest .

1.5. Safe Surfing : https protocolç

This web communication encryption protocol is a secure version of the http protocol
web , and is common in communications with banks, online stores and
private services. When you access a page that requires this protocol
client browser and server agree on making a communication
encrypted. Often some browsers indicate access to this service
using a padlock icon .

1.6. Safe Surfing : digital certificate

A digital certificate (also known as certificate
public key or identity certificate ) is a document
whereby a digital certification authority
ensures the link between the identity of a subject or
entity (for example, name, address and other aspects of
ID) and public key .
One element that can be used as
digital certificate is an electronic ID .

domingo, 16 de febrero de 2014

Gimp

In this term we're going to work with a program called Gimp and we're going to edit images with this programme. Here we have my first work.


Informatic webs

A web is a set of computers conected between them that can  share data and means.

Types:

-PAN: Personal Area Networks.
-LAN: Local Area Networks.
-MAN: Metropolitan Area Networks.
-WAN: Wide Area Networks.

According to their privacy:

-Internet.
-Intranet.
-Extranet.
.Client-server.
-P2P (peer to peer).

Routers:

-With cables.
-Without cables.
-USB.

Inalambric conections:

-IR.
-Bluetooth.
-WiFi.

QR Codes


What is a QR Code? 

A QR code  (abbreviated from Quick Response Code) is the trademark for a type of matrix barcode (or two-dimensional barcode) first designed for the automotive industry in Japan. A barcode is a machine-readable optical label that contains information about the item to which it is attached. A QR code uses four standardized encoding modes (numeric, alphanumeric, byte / binary, and kanji) to efficiently store data; extensions may also be used.

Storage. 

The amount of data you can store depends on three factors: the type (numeric, alphanumeric ...) data, version (indicates the density of the QR code) the level of error correction (higher error correction, lower capacity).

Data Types

-Numeric only. Max. 187 characters (0, 1, 2, 3, 4, 5, 6, 7, 8, 9)
-Alphanumeric. Max. 114 characters (0-9, AZ [uppercase only]) -.> Less than Twitter.
-Binary / Byte Max. 78 characters .

Surely, this type is the most common, as it is sufficient to store a web address.

Version or Density



Generating QR codes 

These pages take you to generating QR codes:

-Kaywa. Generate your own QR codes, for example, the code in the illustration was created using this page and contains a URL. Use your phone to scan the code and navigate there.
-QR Stuff. QR generates slightly more sophisticated codes. On this page you can generate codes to navigate pages on YouTube, Facebook and LinkedIn, among others.

jueves, 16 de enero de 2014

Phubbing

What is phubbing?

Phubbing (term formed from the English words "phone" and "snubbing") is the act of belittling who accompanies us to pay more attention to mobile or other electronic devices which in person.
90 percent of teens prefer contact via text than face to face.

When it starts?

It began the year 2007 with the birth of the smartphone that synthesizing few inches in the power of a desktop computer. With the ability to stay connected to the Internet anytime and anywhere, this obsessive practice that perpetuate many without even knowing it was generalized.

An example to combat phubbing

When you are eatting with other people, all of the person have to take away the
phone for the table. The first person that use the smartphone have to pay the food.



lunes, 6 de enero de 2014

Selfies

What is a selfie?
A selfie is , a self-portrait . The term is generally used in the Internet world to refer to a self-portrait photography that is published online . Selfies is commonplace in blogs , social networks and Instagram. For the solo traveler a selfie is a very common way to document the places you visit .

The typical selfie is a person holding the camera or mobile device throughout his arm , aiming pointing at himself . Photo includes arm, leaving no doubt that this is a self portrait. There is also a self portrait mode with camera facing a mirror, even some versions include a reflection of flash. As they have become more popular in social networks, have become more sophisticated selfies more , to the point that some do not include the camera or phone that took the picture .
The selfies typically include only the photographer.
The number of self-portraits online has grown in proportion to the popularity of social networks in combination with the popularity and spread of use of mobile devices with camera. Even such devices already have features that make it easier to take selfies .
The motivation behind a selfie is difficult to point out .
The reasons most commonly cited are:
Draw the attention of others.
Raise your self-esteem.
Boast achievements or moments .
As a message for a specific person.
For fun .

It is very common to find the hashtag # me together with selfies . In mid- 2013 , # I was ranked among the five most popular hashtags on Instagram.

The word selfie is already included as a valid word in the Oxford English dictionary online.

How to take a good selfie ?
1.Make sure there is enough light. If natural light is better , trying to find the angle and intensity that is most beneficial to you.
2.The extended arm is no longer in use. The mirror or a tripod are better choices.
3.Seeks to exploit your "good side" . Photo rules typically indicate that the camera is placed at eye level and angled , not straight .
4.If the photo is Length , try to take the camera to the waist .
5.If you intend to take during a trip selfies , practice. Be sure you know how far and what angles are the best for you to use.

we can find a very clear example of selfies on  Auryn's Instagram.:

Álvaro Auryn selfies















Blas Auryn selfies
















Carlos Auryn selfies
















Dani Auryn selfies















David Auryn selfies


















My best selfies