Gravity has a familiar physical meaning but also a nonphysical meaningâbasically seriousness. Thus, something grave possesses gravity. You can refer to the gravity of a person's manner, though public figures today seem to have a lot less gravity than they used to have. Or you can talk about a grave situation, as in the example sentence.
A wiki is a website where users can add, remove, and edit every page using a web browser. It's so terrifically easy for people to jump in and revise pages that wikis are becoming known as the tool of choice for large, multiple-participant projects.
The World Wide Web. The World Wide Web (WWW or Web for short) is the part of the Internet that you can access using a web browser such as Internet Explorer or Firefox. It consists of a large number of web servers that host websites. Each website will normally consist of a number of web pages.