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 most important web page on a website is the index page. Depending on the web server settings, the index page can have any name, but the most common names are index.html and index.php. When a browser visits the homepage of a website or any URL pointing to a directory rather than a specific file, the web server serves the index page.