What it google webmaster central?
I have heard somewhere but not got the clear expalantion.
Is it really useful as seo purpose?
When you join in it, you can do some reasearch about your site,just like how many backlinks your site have,which rank your keyword have,etc
Visit and read more documentation there
Unequivocally yes! I say that because it is essential to SEO that a website run cleanly and smoothly. For example imagine that a search engine comes to crawl your site and highly valuable pages aren’t able to be crawled for some reason, it’s pretty easy to imagine how well an uncrawlable page is going to rank.
To answer your question, Google Webmaster Central is a resource for people using Google Webmaster Tools. Webmaster tools provides a user with basic information about how Google is seeing their site. Specifically what are search terms the site is being displayed for, what terms are being clicked through on, errors that are being found (404s, xml sitemap, etc).