How does the computor analysis score the things eg. is +0.12 good or bag,explain!

Thanks! 

i THINK + IS GOOD AND - IS BAD

I think the number indicates how good or bad!

Don

Some chess engines use the standard that + indicates advantage for white while - indicates advantage for black. On the other hand, some engines use the standard that + indicates advantage for whoevers move was and - indicates disadvantage for whoevers move it was. 

Im sure the website for the engine will tell how it scores positions (if you're question pertains to the computer analysis on this site, I believe that they use the + is advantage for white system.)

The number indicates how many pawns ahead a certain player is.  + is for White and - is for Black.  Generally, anything from 0 to .25 is equal, anything from .25 to .75 is a slight advantage, anything from .75 to 1.5 is a clear advantage, and anything above 1.5 is a decisive advantage.