Binary Numbers and Base 2 Calculation for Longs

I was recently looking into this and found it very interesting how simple it was to convert binary into a number with base 2. I understand the highest number a bite can hold is 256 and I'm assuming whenintegers hold a maximum value of 1024 it would be four bites (Each of them being added together).

Longs hold much higher numbers though, so it got me wondering, how big are longs generally? What's the highest value they can hold and how many bites are they usually?