Read the description carefully. Beware of listings claiming that the computer will have Tiger operating system installed. G3 Mac computers or laptops usually have a CD drive. The usually came loaded with a Classic operating system - but often could be later upgraded to OSX (Puma, Jaguar and Panther). However, in order to have Tiger 10.4 operating system installed, it is necessary to have a DVD drive. That's because Tiger 10.4 is on a DVD - not a CD. Also, if you plan to buy the DVD and install it yourself - be sure that you have the correct version of Tiger 10.4 for your laptop. (Some are for Mac desktop computers and others are for Mac laptop computers.) And also note that the software may only install on a G4 Mac laptop. So if you have a G3 Mac computer, it may not work.