How does a USB drive work

I have wondered for as long as They existed. How do They work? USBs are the most oddly useful doodads on a computer and I would like to make something to be powered from one. In short, How?

110100101108 years ago
usb has 2 entries for 5 V supply and 2 for link the usb drive contains a flash chip (rectangular one with connection along the short sides) that actually stores the files and other chip (usually small square) that connectss the flash chip and the usb. it sends data in and out of the flash chip and the computer sees only it (not the flash chip) thru the usb as mass storage device to power stuff from usb you dont need any of the chips. if you look into the usb ports on the back of a normal pc then the top entry is + 5 V and the bottom is earth. it can supply up to 500 mA (in many computers up to 1 A if the other port of the 2 ports that are together is not used)
Bigev (author)  110100101108 years ago
Wait wait, which ones are the data and which ones are the +/- 5V? Going from left to right with the plastic tabbie on the top.
5V link link earth
Bigev (author)  110100101108 years ago
Many thanks!