When you follow people on twittter, do they in turn follow you?

[Renesme]

Or is it an option they have to seek out themselves. I am new to twitter and have no followers yet! lolm I am curious how it all works.
Cheers.
PS- know any interesting people for me to follow on twitter?

[Sam728]

They have to physically click the follow button on your profile, however they will be told you now follow them

[Windowphobe]

I follow about 60 people who don't follow me. Then again, there are about 50 people following me whom I don't follow.

If somebody follows you, you will be sent an email telling you so, as follows:

Hi yourname (yourTwittername),

Somebody (somebody'sTwittername) is now following your tweets on Twitter.

Check out Somebody's profile here:
http://twitter.com/somebody'sTwittername

You may follow Somebody as well by clicking on the "follow" button.
Best,
Twitter

So there's the option.

I follow, among others, "Weird Al" Yankovic and Queen Rania of Jordan, neither of whom are following me.