Programs such as Skype or GoToMeeting are web-hosted services that allow for desktop sharing, online meeting and video conferencing via the internet. Usually a microphone and/or webcam are required. Most have a chat functionality built in as well, for those who may not have access to a webcam.
You may come across references to 'webinars'; these are usually online workshops or sessions run using these kind of applications. It means the participants can all engage and communicate in real time from very different and widespread locations.
A social bookmarking service is an online service which enables users to create bookmarks of online documents and websites, as well as add notes and share bookmarks with other users. The bookmarks are all web-based, which means you can access your account from anywhere, rather than being tied to computer-based 'favourites'.
'Tagging' is also a major feature of most social bookmarking systems; tagging is basically the online equivalent of assigning keywords or terms to the bookmarks you have made, for your own ease of organisations and also so that others can find material relevant to their interests, hence the 'social' aspect of social bookmarking.
A social news website features stories posted by individual users that are then usually ranked on popularity. You can comment on these posts, and those comments may also be ranked. Many major news outlets will have a presence on social news sites, which means it is not just user-centric stories and posts, but also 'real' news articles.
Many sites can be customised to your interests, so you can browse stories on particular topics or keywords. Some also 'learn' your interests based on how you rank articles, in order to deliver more relevant results.
Social project management tools are designed to assist in the organisation and performance of project management using cloud-based software, accessible from anywhere.
Communication can often deteriorate when teams do not work together or meet frequently. As a result, tools such as Basecamp or Huddle apply social networking to facilitate communication and content sharing between distant or virtual teams. Many such services combine multiple social media aspects, including video conferencing, social bookmarking etc.
A wiki is basically a collaboratively-edited website, usually using simplified web-coding software. It is generally associated with websites such as Wikipedia, which is a crowd-sourced or collaborative encyclopedia. All users can create or edit pages, and add notes or discussions regarding changes they have made.
Wikis can be used for all kinds of collaborative purposes, including intranets, note-taking, document-sharing and other forms of knowledge management. It is not generally designed to be a public-facing website, due to the basic nature of the interface and layout and the constantly-changing content.
Social bibliography sites are primarily aimed at the academic and research community, for facilitating the sharing of references amongst academics, researchers and students. Sites such as Mendeley permit users to upload details of their own publications, which can be bookmarked by other users for future reference. Many also combine this function with reference management software that will harvest links, extract metadate and create bibliographies.
Social document sites such as Google Docs allow users to upload documents that can then be shared with others. Documents can then be accessed and edited from anywhere via the internet. You can also specify the level of access granted to others, so documents may only be viewed or you can grant editing rights.