Yes, Lily. They're both places where people rent space (called a booth (sing.) or booths( plural)) to sell their stuff. Swap meets are a little more interesting because booths rent for a few days; therefore, each week has new sellers. Leases at flea markets are for longer periods, one month to several months, so the offerings don't change as frequently. Also, swap meets are more for hobbyists, like a knitter selling her crafts or a record collector selling his old albums (or sometimes the sellers even swapping what they have for what you have), whereas flea markets are more for commercial goods.