help?

[sparklethedarkx.livejournal.com]

So I'm kind of new to the language, and a few things have been nagging at my mind and making it more difficult to comprehend.  I understand most of the alphabet, except for two letters:

"the hard sign" ъ
and
"the soft sign" ь

I've tried to find their meanings on a few different websites, and I've asked my Russian friend, but her english isn't too good, so I could not really understand.  What do they really mean?