"Deer" is sort of a generic term. It encompasses what most people think of as deer (below)...
Columbian blacktail deer (Odocoileus hemionus columbianus), range: northern California, north through western Oregon, Washington, and British Columbia.
Coues' deer (Odocoileus virginianus couesi), range: Arizona, New Mexico, and Northern Mexico.
Mule deer (Odocoileus hemionus), range: the western half of North America, from the Yukon south to Mexico, east from the peaks of the Cascades and Sierras, over the Rockies into the US and Canadian prairies.
Whitetail deer (Odocoileus virginianus), range: all of North America (US, Canada, and Mexico).
Sitka deer (O. h. sitkensis), range: Alaska
Florida deer (O. v. clavium), range: primarily the Florida Everglades.
...as well as moose, elk, and caribou which are also species of deer.
There are many different types of deer. Some of the types of
deer include white tailed deer, moose, mule deer, caribou, sika
deer, sambar and fallow deer.