"Social networking" has been around forever. It's the simple act of expanding the number of people you know by meeting your friends' friends, their friends' friends and so on. In fact, many of us today use Twitter and Facebook to promote our existing and upcoming business
After observing and running an analysis some of Social Networking sites I have listed down 5 most popular social networks across countries in detail.
1.
Facebook
founder: Mark Zuckerberg
To access Facebook.com, you must create an account on the site which is free. Facebook's terms of use state that members must be at least 13 years old with valid email ID’s. After updating you're details, your Facebook profile is generated. Using Facebook.com you can:
- Browse and join networks, which are organized into four categories: regions, colleges, workplaces and high schools.
- Pull contacts from a Web-based e-mail account, into Facebook.com.
- Find friends in several ways, including search engine to look for a specific person and lot more.
- Facebook has recently crossed 500 million users and is the most popular Social Networking site of the world.
2.
MySpace 
founder: Tom Anderson, Chris DeWolfe In MySpace, your social network starts growing from the first day. When you join MySpace, the first step is to create a profile. You then, invite friends to join there and search for your friends on already profiled on MySpace these friends become your initial Friend Space. Once the friendship is confirmed all the people in your friends' Friend Space become part of your network. In that sense, everyone on MySpace is in your Extended Network. As part of terms of MySpace, the user must be at least 14 years old to register. 3.
Twitter 
founder: Evan Williams, Jack Dorsey, Biz Stone Twitter is a very simple service that is rapidly becoming one of the most talked-about social networking service providers. When you have a Twitter account, you can use the service to post and receive messages to a network of contacts, as opposed to send bulk email messages. You can build your network of contacts, and invite others to receive your Tweets, and can follow other members' posts. Twitter makes it easy to opt into or out of networks. Additionally, you can choose to stop following a specific person’s feed. 4.
LinkedIn 
founder: Reid Hoffman, Konstantin Guericke, Allen Blue LinkedIn is an online social network for business professionals, which is designed specifically for professional networking, to help them find a job, discover sales leads, connect with potential business partners. Unlike most of the other social networks, LinkedIn does not focus on making friends or sharing media like photos, videos and music. To start using LinkedIn you need to register and create a profile page. To register to LinkedIn, you need to provide personal information. You can update the profile with your education and job details and a summary. Additionally, you can also give and receive recommendations from co-workers and bosses. There are more than 75 million professionals registered on LinkedIn. 5.
Pinterest 
founder: Ben Silbermann
Pinterest is a social networking site with a visually-pleasing “virtual pinboard” interface. Users collect photos and link to products they love, creating their own pinboards and following the pinboards of other people whom they find interesting.