Meaning – The term keyword, refers to a lexical unit that, in certain contexts, characterizes some language construct; for example, in some contexts, IF characterizes an if-statement. A keyword normally has the form of an identifier.
It also refers to one of the predefined words of an artificial language.
A user may “tag” pictures or text files with keywords that are relevant to their content. Later on, these files may be searched using keywords, which can make finding files much easier.
Keywords are used on the Web in two different ways:
1) as search terms for search engines, and
2) words that identify the content of the website.
Example of usage – “Whenever you search for something using a search engine, you type keywords that tell the search engine what to search for. The search engine will then return Web pages with content relevant to your search terms.”