How do Pros manage backup?

This week a horrible thing happened. Ad mentioned in my other post, i lost my time machine drive to some form of hardware/software corruption. And i did the huge mistake of cut-pasting my archived iPhoto library onto the same media! Today i realized that i didn't have a single copy left of the 10 year of photographs!!!

Infact, before i realized that my iPhoto library was on it, i even made an attempt to erase the partition! Luckily, it failed. I am glad that i wasn't able to erase the drive.

Now i have deployed 'data rescue 3' for the job of recovering my drive.

But i learnt an important lesson the hard way, to not depend on one physical media for backups! I had also almost ordered the LaCie cloud box 4tb nas storage when i learnt from the internet that its a single hdd inside. That simply means i was about to repeat the disaster on a much bigger level a few years down the lane.

So can someone tell me how Pros manage backup? What form of media they use and what configuration?

Should i order to nas storages and make one clone the other? I have absolutely no knowledge how ill manage that with a single lan port on my airport express!

Or can u link me to a good read online? Something that clears my mind about this subject?

How do u manage backup?