ok, so think of it like a penny arcade. you give the cashier 1 dollar and she gives you 10 tokens, which you can spend in the arcade. When you leave, you cash in your remaining tokens.
Bitcoins are send yo the account to get credits and then bitcoins are sent back to client when they cash in their credits. That is how the coins are used.
Now, i assume (perhaps in error) that the mtgox's and blockchain of the world have better security than i can privide while allowing me to receive/send bitcoins.
If I do not keep them online anywhere, how does that work? Do I send all the accumulated coins to my private wallet every hour, and then make a cd backup of that wallet every hour?
Regardless of how I use the coins, the question is the same: What is the best way to make an online wallet secure?
It starts with you, it is more likely that your computer got compromised or email then all those services you used suddenly got hacked to get to your coins. I'd advise to first make sure the computers you use are well secured and you know enough on how to keep them secure. Second, if you trade on an exchange don't leave large chunks online but only what you can afford to lose. Third, if you run your own online business with an online wallet make sure to empty it often so if something happens it'll not cause you a serious loss and invest in the security of your business.