Modern
Pointed Collar
The turned down, pointed collar is the collar most commonly found on shirts
today. They come in a wide variety of lengths, degree of pointedness, and
amount of spread. A wider spread collar is useful for larger ties such as
ascots.
These are certainly acceptable for steampunk, although many people eventually
strive to find less common collars (see below). You can sometimes modify a
pointed collar, such as turning it up (into a stand up collar) or ironing the
tips into a wing collar, and then adding a tie that keeps the collar
upright.
Band
Collar / Mandarin Collar / Collarless Shirt
A band collar is a good collar for a workman's shirt. It generally does not go
with a tie for practical reasons. A band collar also allows the addition of a
detachable collar. Some are even constructed specifically for the purpose.
Similar-looking collars can be found on modern "collarless" shirts, which are commonly used. Some are less stiff in apperance than the band collar, and the collar may taper to a slight V in the front, with the first button sitting below the collar instead of being a part of it.
Club
Collar
Pretty much an all-purpose collar, similar to a spread collar of today, minus
the pointedness.
Stand Up
Collar
Worn stiff, this is a formal and professional collar. Less stiff, and it it can
be more widely applicable. The stand up collar allows for very large cravats
and other neckwear to be worn without interference from the collar.
Wing
Collar
The wing collar is a sort of cross between the stand up collar and the modern
turned down pointed collar. Highly formal, it allows for a wide range of ties
and cravats.
To consider what sort of neckwear might go with your collar, check out The Ties that Bind.
Photos (c) The Gentleman's Emporium, used with permission.