How can i add metatags to my blog

I whant to add the metatags description and keyword in the main page at my blog how can i do this ?

Olso well my title i whant it change but (see http://www.funny-stuff.net )
the write on the blue (witch is the same as the title now i whant it like now becouse when i change from the admin it changes autmaticaly not only the PAGE TITLE olso the writing beside created by w3bmaster and that i whant to stay that way)

Thanks in advance

 

Edit the "header.php" template file.

 

Ok thanks for the answer

 

The Ultimate Tag Warrior plug in automatically adds meta tags to your wordpress posts.

 

If you do not want to use a plug-in, you might wanna consider this

Hope that helps