novice USB & data acquisition

Hi: I would like advice on where to begin. I'm interested in making a
data acqusition system (simple simple simple) that can write the
collected data to a flash drive. To do this I need to know:

1) How to create a USB interface that a flash drive can be plugged
into and my device (yet to be created) can write data files to.

While this is a very straight forward idea, i have some
microcontroller, memory, and USB pieces to learn. I'm a EE but never
had more than just basic microcontroller's in school. I'm not in a big
hurry and I'm talking small scale and as simple as possible.

best regards,
russ

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