"Color Space" basically means how color is produced. Something to keep in mind is that when we are going back and forth via our computers picking colors for your logo, we are both looking at the mock-ups in a RGB color space.
RGB (RED - GREEN - BLUE) is an additive color space. Computer display started off as black and through the addition of light a whole range of colors are produced from a small set of primary colors.
Red+Green+Blue=White
When you have your logo to go to print, its colors are going to be produced in CMYK model. Also known as the four color process
CMYK (Cyan-Magenta-Yellow-blacK) is a subtractive color space. The colors are produced through a combination of these tints. How the ink absorbs or reflects light produces color.
Cyan+Magenta+Yellow=Black
The colors in the RGB model are much brighter than the colors in the CMYK model. CMYK has a more limited color spectrum due to the nature of reflected light.
PANTONE (PMS) is also considered a " color space" that is proprietary. There are certain sets of pantones that can be reproduced through CMYK process . (Please click below to view which ones they are.) But most of the Pantone systems are spot colors and are only produced by 13 base pigments mixed in specified amounts such as metallics and fluorescents. If you are picking one of these spot colors it will be more expense to produce.