Paso Finos:Gaits:
Paso Fino (literal translation is fine step. Even timed four bead, collected, slow to medium speed)
Fino Fino (very fine step. Show gait, even timed four beat, very slow forward movement, in high collection, high frequency)
Paso Corto (short step, even timed four beat, longer than the Paso Fino)
Paso Largo (long step, even timed four beat, ground covering, fast)
Trocha (trotty four beat, equal to foxtrot walk and canter trot also.
Note that some of the Columbian lines are "trote y galope" horses, ie:
no ambling gaits. Horses are shown either trote y galope, trocha or fino.

Links for Paso Finos:
http://en.wikipedia.org/wiki/Paso_Fino
http://www.pfha.org/the-breed/breed-standard
http://www.gaitedhorses.net/BreedArticles/PFBreedStandard.html
http://www.yeawedo.com/pasofinohistory.htm

There are two main areas where they are bred, and two (more or less) distinct types:
Puerto Rican and Columbian
In Oz, we have mainly PR lines.  Jorge de Moya, who imported them for the first time in 2000, brought horses of PR descent.
Only a couple of the mares had a little Columbian blood, and one of the imported geldings is mainly Columbian.
Narrawin Stud's new stallion "Reverende de United" is from all Columbian lines.

More info about the differences here:
http://puertoricanpasofino.org/history.html