Is this a good robots.txt ?

My robots.txt file goes like this:

User-agent: *
Disallow:

Code (markup):

Is that okay? Does it block anything?

 

That is telling all the bots to block nothing.

In this case you typically don't have a robots.txt file at all.

 

You don;t need a robots.txt file if you wish to have these settings.

 

if you really want to disallow then try

User-agent: *
Disallow: /
it will disallow all pages to all search engine to crawl,

if you want to disallow any particular page then put your page name instead of /