For Canon? (EOS lenses 1987 till today)
EF-S = 1.6x only.
EF = can fit all current models.
L = can fit all current models.
For Nikon? (lenses from 1959 till today)
DX in the lens name = meant for 1.5x. But will fit FF bodies also. Some will vignette. Some ok at certain focal lengths. If you set FF body to digital crop mode, the lenses will work just like a DX cam.
AF-S, AF-I, without DX label = can fit all current models with full functionality.
AF-D, AF = can fit all models. AF only on D90/D80/D70/D50 and above model lines
Ai, Ais, Ai'd = can fit all models, MF only, metering only on D300(s)/D200/D100 and above model lines.
Pre-Ai = can fit only D5000 D3000 D60 D40x D40 models. MF, M mode with no metering.
You can check with the respective 3rd party lens manufacturer web sites. Usually they state whether the lens can be used with 'Digital SLR'. Although a bit misleading, most of them use this term to refer to any form of crop sensor body.