Keywords are words or phrases that describe the content. They can describe images, text documents, database records, and web pages based on metadata.
A user can easily “tag” pictures or text files by using relevant keywords according to their content. Later, these files can also be searched using keywords, making it much easier to find files.
For example, a photographer uses a program such as Apple iPhoto to tag his nature photos with words such as “nature,” “trees,” “flowers,” “landscape,” etc. By tagging photos like this, he can easily locate all the flower pictures later by simply searching for the keyword “flowers”.
Keywords are used on the Web mainly in two ways,
1) first in search engines as search terms, and
2) Words that can identify the content of the website.
1. Search Engine Search Terms
Whenever you do some search in a search engine, then in this way, we type keywords that tell the search engine what to search.
For example, if you are searching for used cars, you will enter “used cars” on the keywords.
Then the search engine will automatically show such web pages in SERP (Search Engine Result Pages), which is relevant according to your search terms.
While the more specific keywords you use, the more specific (and useful) your results will also be. So if you are searching for a specific used car, you have to enter some keywords such as “Blue Honda Maruti Suzuki used car”, from which you will get the best accurate results.
Many search engines support boolean operators, which can be used with keywords so that the search can be refined more.
For example, you can search “Apple AND computers NOT fruit” if you only want information related to Apple products and not Apple information of a fruit.
2. Web Page Description Terms
Keywords can also describe the content of a web page. This tag is placed in the HTML of a page in the section and contains all the words that describe the Web page’s content.
The main purpose of the keywords meta tag is to help search engines identify and organise web pages.
But since web admins use inaccurate tags to get higher search engine ranking, many search engines give very little importance to keywords meta-tag when indexing pages.