Skippers, as a group, are among the most difficult butterflies to identify. Most of them have some variation of pale orange with dark brown markings, and occasionally a white spot or two. Skippers can be identified more easily if you know what is flying. This is not always obvious from field guides since the peak dates vary by region. It seems that the best way to learn is by watching skippers over a few seasons. These skippers are a few that I photographed near the end of August and beginning of September.
This first is a Sachem (Atalopedes campestris), a common skipper in late summer and fall. Sachems always leave me a little uncertain because their markings seem especially cryptic, even for skippers. I usually try to eliminate other possibilities as best as possible before settling on an ID. This Sachem is nectaring at a butterfly bush.
The second is a Little Glassywing (Pompeius verna). These are dark butterflies with white spots on the wings. According to my field guide, the white markings just below the tips of the antennae are a distinctive field mark. That helps a lot since the rest of this skipper's markings do not seem all that distinctive.
The last is a Zabulon Skipper (Poanes zabulon), a common late summer skipper. This is probably the skipper species I see most in August. Since August I have seen mostly Sachems. The Kaufman guide shows a yellow spot surrounded by brown at the base of the wings; this seems to be a feature only of the hindwing. I like how this skipper has its proboscis rolled up. In some photos before I took this one, it was nectaring at the phlox.