A word or set of words which play a key role to find out the webs through Search Engine is called keyword.
A keyword is a text record in the indexed data or document that search string brings the web pages on the basis of its relevancy.
So, a word which goes through a search engine and catch by its search string to find out the relevant documents from the previously indexed data, then presents in the search engine result pages is called a keyword.
Keywords play a very important role in the optimization of a site for expected ranking. On the basis of keyword relevancy, keyword length, keyword compatibility and rightly selected keyword boost a site’s rank towards apex.
Keyword research is a sagacious conduct done by SEO professionals to obtain significant searching keywords relevant to the site’s targets that people use in the search engines during their searching. The aim of the skillful Keyword Research is to achieve a set of very relevant Keywords so that they boost the ranking in a natural SEO. There are many research tools in webs for significant keyword findings, Google Adwords Keyword Tool is enough one of them.