If it breaks off in your fingers because each strand is soooo thin and delicate, you have fine hair.  If you could use it for rope because it is soooo strong, it is coarse.  If neither one of those apply, it is medium.

I borrowed this from Fia at www.longhaircommunity.com :

F - Fine
Thin strands that sometimes are almost translucent when held up to the light. Shed strands can be hard to see even against a contrasting background. Similar to hair found on many people of Scandinavian descent.

You can also try rolling a strand between your thumb and index finger. Fine hair is difficult to feel or it feels like an ultra-fine strand of silk

M - Medium
Strands are neither fine nor coarse. Similar to hair found on many Caucasians.

You can also try rolling a strand between your thumb and index finger. Medium hair feels like a cotton thread. You can feel it, but it isn't stiff or rough. It is neither fine or coarse.

C - Coarse
Thick strands that where shed strands usually are easily identified against most backgrounds. Similar to hair found on many people of Asian or native American descent.

You can also try rolling a strand between your thumb and index finger. Coarse hair feels hard and wiry. As you roll it back and forth, you may actually hear it.

I have seen posts with this 1a and 1b for hair types (and ones that are 3a and 3b).  Come someone direct me to where I can read about what this means?  Thanx.

Thanks a bunch.  I am a 1b.  Now I know.