terminology - What is the effect where some objects are a single bright color but the rest is black and white?

There is an option to filter only one color (R,G,B,Y) in my camera. What I want to know is can this effect be achieved in photoshop? And what is this called? I tried googling monochrome and came up with nothing. My camera calls it part color.

Answer

This technique is called Selective color.

Sometimes, you select a point (in this case, somewhere on the CD-R case), and the region around that point that is close enough to the same color retains its color, while the rest of the picture becomes black and white.

Other times, as you mention, you can select a color and a tolerance, or a range of colors, and the software will allow anything within that range to remain colored.

On the example on the Wikipedia page, it appears that the saturated region was hand-selected or masked.