Cross Linking?

What exactly is cross linking?

[cheater copperpot]

Hello all, I am new to the world of SEO etc and I have a question for all of you Gods out there. I have a few sites now that focus on "nearly" the same topic. And i want to link to all of my domains from each seperate one.

Heres an example: My main site sells widgets, but i also have 4 other more specific sites that sell blue widgets, green widgets, yellow widgets, white widgets. So I want to put links to all of my pages from each seperate page (does that make sense?)
Is this considered cross linking? And will i be penalized for it? Thanks in advance...

[Thors Hammer]

LOL, this subject just came up in another area, take a look at this it might help..

[webmasterworld.com...]

Thor