Dob - Dobsonian: It is a type of mount that is popular because (a) cheap for the aperture it can hold (b) in general robust and (c) simple.
It is basically an alt-azimuth mount and is used for Reflectors. Picture this: Typically looks like a box that is on a restaurant style lazy-susan type arrangement (i.e. a base-plate with turn-table) all of which rests on the ground - so you were almost right
. Visit almost any telescope selling web-site and you will see 6" (and larger) reflectors for sale on Dobsonian mounts for, in general, quite a bit less than an AZ or EQ mount - does not have tripod legs etc. Can have other advantages but as with everything else there is a trade off. Dob mounts have made access to large apertures for sensible budgets just that bit easier. BTW general range for dobs seems to be from about 6" to 12" due to size of the mirror and length of the tube. Can get larger but step ladders then become mandatory and perhaps paid up health insurance.
If you end up deciding to get a telescope, I'd recommend buying from a telescope dealer such as some of the ones listed already in this thread or who are linked to this site. Please stay clear of the department store "cheap" scopes as realistically they are not "cheap" and have pitfalls.
BTW If you have binoculars then have them handy near the telescope when starting out. They make matching what you see with charts that much easier and help familiarisation before getting the finder of the telescope in the right area and then the "looking through a straw" telescope field of view.
Be curious to hear what you might decide.
Merry Christmas. Or if you are from the states "Happy Holidays".