Social network services

A social networking service (also social networking site, SNS or social media) is an online platform which people use to build social networks or social relations with other people who share similar personal or career interests, activities, backgrounds or real-life connections. The variety of stand-alone and built-in social networking services currently available online introduces challenges of definition; however, there are some common features:

Most social-network services are web-based and provide means for users to interact over the Internet, such as by e-mail, by instant messaging and through online forums.

Social networking sites are varied. They can incorporate a range of new information and communication tools, operating on desktop and laptops, mobile devices such as tablet computers and smartphones, and featuring digital photo/video/sharing and "web logging" diary entries online (blogging).Online community services are sometimes considered social-network services, though in a broader sense, a social-network service usually means an individual-centered service whereas online community services are group-centered. Social networking sites allow users to share ideas, digital photos and videos, posts, and to inform others about online or real-world activities and events with people in their network. While in-person social networking, such as gathering in a village market to talk about events has existed since the earliest development of towns, the Web enables people to connect with others who live in different locations, ranging from across a city to across the world. Depending on the social media platform, members may be able to contact any other member. In other cases, members can contact anyone they have a connection to, and subsequently anyone that contact has a connection to, and so on. LinkedIn, a career social-networking service, generally requires that a member personally know another member in real life before they contact them online. Some services require members to have a preexisting connection to contact other members.

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Wikipedia