Smoke results from combustion at 800-1000F. Vapor results from vaporization at lower temperatures, typically around 400F for cannabis.
Vapor contains as much as 83% less tar and other unwanted products than smoke.
Vaporizers can range from 150$ all the way up to several hundreds (as much as 800$ in the case of the Volcano).
A model I often suggest is the Arizer Solo (~ 200$
here) due to its portability, convenience and build quality.
In the picture above the Solo is interfaced with a water filtration apparatus ("bubbler" in the jargon). The vapor is generated by the Solo, then is diffused in the water. The water catches matter and particulates that are basically pollutants. Then the vapor comes out of the water filtered and enters your lungs. The result is vapor that is almost pure H20+cannabinoids.
Alternatively, you can use the vaporizer alone ("solo") with some of the glass attachments that come with it. They're basically glass straws which you "plug" into the Solo and pull on it like you would on a drink.
The solo has the merit of being portable because it contains a lithium battery and as you can see in the picture above, it is very small (fits in the palm of an adult hand).