help with bits please

[db12345]

hello i recently receved a metal lathe / mill combo and have done a bit of machineing previously in scholl and was wondering , if their is a reason these bits are color coeded i have sets of each of the colors the black , red , bronze and grey bits any ideas ?

also could you please guid me to some pages with tips and different toolings i got alot of bits and was wondering what i can do with them