L

Layers

Attribute in CSS. A rectangular section, or layer, of HTML code that can be placed on a web page by assigning X, Y, and Z coordinates, measured in pixels.

Link farm

A collection of indiscriminate, often unrelated, web sites that link to each other to artificially boost link popularity.

Link popularity

Refers to the number and quality of inbound links to a web site from other web sites. One of the highest quality inbound links is a link from a major directory such as Yahoo!.

Link rot or linkrot

A link from a search engine, directory, or other web site that results in a 404 error page after a web developer modifies a web site with new URLs or removes pages from a web server.