paramater handling help

Could someone give me a crash course on parameter handling

I got into my blogs sites in google webmaster tools and I see under

Site configuration
Settings
Paramater handling

a bunuch of parameters such as
id
s
sort
cat
p

what are these, should ignore them? whats the deal?

Cheers and thanks

Set all parameters which does have nothing todo with your content on the page to ignore. Example if you have the following url:


Than you can ignore the parameter, because you dont want to get a lot of pages with the same content indexed.

cool but what if i have something like the letter "p" if i put that in there will it ignore all links starting with p in the final part? I can understand sort and such...

do all paramaters start with ? then the url so if it says "p" in the parameters section are we talking
domainname/somelink?p

or would it block like domainname/peaches because peaches starts with p haha make sense?