Allows you to customize the way a web page displays or behaves, by using small bits of JavaScript. You can write your own scripts, too. Check out http://wiki.greasespot.net/ to get started. Many scripts already exist, probably ones to enhance your favorite sites. Find them at http://wiki.greasespot.net/User_Script_Hosting . Having trouble? Please don't post comments here, nobody will see them. If
![greasemonkey](https://cdn-ak-scissors.b.st-hatena.com/image/square/e08f6250bd49edaefca22b3a5dc08cdb5825d06d/height=288;version=1;width=512/https%3A%2F%2Faddons.mozilla.org%2Fuser-media%2Fpreviews%2Ffull%2F192%2F192024.png%3Fmodified%3D1622132241)