I believe you should do some basic searching before you ask such questions. A simple google search would give you two good pages (wikipedia and wordtracker). Come back here with more intelligent questions and all of us will have a good discussion. To get you started, keyword research is the process to find keywords with good amount of traffic and potentially good sales / ad revenues while ensuring the competition is limited.
111 posts and asking what KW research is? GTFO you trolling bastard - you're just trying to dump your sig links. I wish posters like these would be banned instantly!
keyword research is seo analysis , researching keywords for a specific topic that would presumibly give you higher recognition among search engines
keywords reaches is the base of any gud seo company and large amount of your success with truly dependent on how well you did your keywords reaches. of course, this will be built into overall seo strategy but it should be the very first item on your to do list.
I think the phrase "keyword research" clearly explains the meaning itself. Anyways, you can always refer on search engines if you can't get good or enough answers here.
You are right mate don't know why people ask this kind of questions. Keyword Research is the process for finding best possible keyword for your site.