I have a flat iron, which I use on the lowest heat setting to give lift to the crown of my chin-length hairstyle and to flip the ends under, a final touch after applying gel and blowing almost dry. I comb out a thick section of hair, clamp it in the iron near my roots, tilt the iron down 180 degrees and gently pull the hair all the way through.

My friend uses her flat iron to give a straight style to her curly hair, which I think is more common.

Usually curling irons are used to give a curly style.

With any of these heated tools, be very careful not to burn your fingers and remember to unplug them and put them away when you're finished (otherwise they could easily fall into the sink or bathtub and cause a shock).