[TYPO3] Editing the <title> tag for specific pages?

[Amir M.]

Hi,

I have a website with 3 subsites, each subsite using its own subdomain, 
however they all use the same root template.  I would like to know how 
can I customize the <title> tags for each subsite and its pages?

I would assume this is possible with extension templates?  If it is, 
what TS Code do I use to make this possible?

And if this is possible, is it also possible to add unique meta keyword 
tags to specific pages and its subsites.

Thanks