Click on the tab of the person whom you wish to know about. The Shinra tab includes information about Rufus, the Turks, and most of the well known Shinra employees introduced in the game. If you know anymore extra information on these charachters here, please tell me so I can put them up. Of course you'll get the appropriate credit... ^_^
The Sephiroth tab also has some things about Jenova in it. If I get enough requests I'll probably make another page for Jenova, but that doesn't seem likely now.
I basically ruin the history towards the charachters in this section so proceed at your own risk. Don't come complaining to me that I spoiled the story for you >:).