XARXES SOCIALS MARTA GARRIDO

FACEBOOK

Facebook is an online social networking service. Its name comes from a colloquialism for the directory given to students at some American universities. Facebook was founded on February 4, 2004 by Mark Zuckerbergwith his college roommates and fellow Harvard University students Eduardo Saverin, Andrew McCollum, Dustin Moskovitz and Chris Hughes. Users must register before using the site, after which they may create a personal profile, add other users as friends, exchange messages, and receive automatic notifications when they update their profile. At the end of January 2014, 1.23 billion users were active on the website every month, while on December 31, 2013, 945 million of this total were identified by the company as mobile users.
YOUTUBE
YouTube is a video-sharing website, created by three former PayPal employees in February 2005 and owned by Google since late 2006, on which users can upload, view and share videos. YouTube was founded by Chad Hurley, Steve Chen, and Jawed Karim, who were all early employees of PayPal. YouTube says that roughly 60 hours of new videos are uploaded to the site every minute, and that around three quarters of the material comes from outside the U.S.All YouTube users can upload videos up to 15 minutes each in duration. Users who have a good track record of complying with the site's Community Guidelines may be offered the ability to upload videos up to 12 hours in length, which requires verifying the account, normally through a mobile phone. The first YouTube video was entitled Me at the zoo, and shows co-founder Jawed Karim at the San Diego Zoo. The video was uploaded on April 23, 2005, and can still be viewed on the site.
 TWITTER

Twitter is an online social networking and microblogging service that enables users to send and read "tweets", which are text messages limited to 140 characters. Registered users can read and post tweets, but unregistered users can only read them. Twitter was created in March 2006 by Jack Dorsey, Evan Williams, Biz Stone and Noah Glass and by July 2006, the site was launched. The service rapidly gained worldwide popularity, with 500 million registered users in 2012, who posted 340 million tweets for day. Work on the project started on March 21, 2006, when Dorsey published the first Twitter message at 9:50 PM, Pacific Standard Time: "just setting up my twttr". As of February 16, 2014, the following ten individuals and organizations managed the most popular: Katy Perry (50,531,561 followers), Justin Bieber (49,651,896), Barack Obama (41,479,641), Lady Gaga (41,036,706), YouTube (39,456,451), Taylor Swift (39,090,442), Britney Spears (35,921,631), Rihanna (34,147,179), Instagram (30,812,738) and Justin Timberlake (30,654,153).
INSTAGRAM
Instagram is an online photo-sharing, video-sharing and social networking service that enables its users to take pictures and videos, apply digital filters to them, and share them on a variety of social networking services, such as Facebook, Twitter, Tumblr and Flickr. Instagram was created by Kevin Systrom and Mike Krieger and launched in October 2010. In January 2011, Instagram added hashtags to help users discover both photographs and each other and on December 12, 2013, Instagram announced Instagram Direct, a feature allowing users to send photos to specific people only directly from the app. In April 2012, it was announced that over 30 million accounts were set up on Instagram. Many celebrities have profiles on Instagram, sharing photos and videos of their personal and professional lives with fans.