Bowie knife styles are legion; from a simple butcher type knife with a straight spine and no clip (as the original knife carried by mr Bowie on the sandbar most likely was) over a wide variety of knives to over the top clown knives with a very big curved clip, spine strip, oversized hand guard and of a type, which some (utterly scrupulous) persons have bamboozled others into believing was carried at the Alamo......and bamboozled into buying said clown knife.
I like both the aforementioned simple straight spine type Bowie knife and a type of knife with a relatively long drawn back clip.
Nailed it.
There is the sandbar knife. The first Bowie. While there is no definitive proof what it was, it was more than likely one of the Searles knives or the Forrest knife. I think it was the Forrest knife. Beefed up butcher knife meets punal.
http://www.tamu.edu/faculty/ccbn/dewitt/adp/history/bios/bowie/knife_like_bowies.html
Then there are the Bowie era Bowies. Anything went because everyone wanted a Bowie knife, and nobody was sure what it looked like. Folders, daggers, etc etc etc.
Then there is the whole question of what knife Bowie carried at the Alamo. That is less documented than the sandbar knife, it seems.
Then in comes Raymond Thorpe, who invents, based on Scagel knows what, the "original" Bowie. The one BladeScout mentions. Pulls the design out of the ether or something. That design gets crazy popular, they make a movie called The Iron Mistress about Bowie featuring that design, that it gets even more popular.
The sandbar knife was express built as a weapon. Pure and simple.
What is a Bowie now and what is done with it? Just about anything.
If you can get your hands on a copy of Levine's Guide the Knives and Their Values, 4th edition or earlier...he gives a great history based on actual fact and documentation.