/diy/ - Do It Yourself

Achieved a milestone today: I blew up my first component.
Hooked up a photocoupler directly to a power source, completely forgetting that inside is in fact an LED.

/ohm/, I come as a retard asking for guidance.

I've never done any home projects involving electronics, but I've seen people take older models of iPods and give them more storage space. I came across a how-to on imgur where someone added a 480GB mSATA SSD to a 5th generation iPod classic and it had me thinking about doing something similar to a 7th gen with a 1TB drive or something. Compatibility with the iPod's firmware came up somewhere in the how-to, how can you tell what's compatible with what? I don't want to sink money on something then be unable to use it.

I know I sound like a bumbling retard, I just want help.