There have been 4 generations of the Altima, which is pretty amazing when you consider that it has only been around since 1993. The first generation was sold from 1993 to 1997, the second from 1998 to 2001, the third from 2002 to 2006, and the fourth since 2007. Who knows, by the time you read this, the Altima may have undergone another complete overhaul.
This car replaced the Stanza, a car that was not popular with many reviewers or buyers. It would be a compact car until 2002. Despite being a compact car, they were all sold with 4 doors. The base and only engine was a 150 horsepower I4. Transmission was a 5 speed manual or a 4 speed automatic.
The trim lines on the Altima inlcude the XE, which was the base model with manual windows, the GXE, which added a few features like power windows, and the SE, which offered some sporty performance upgrades. The GXE also came in a limited edition package starting in 1997.
Little changed in the second generation other than some new options.
The third generation saw the introduction of a V6 engine making 240 horsepower. That engine was available on the SE-R model and some other trims and as an option. That engine helped the Altima beat every car in its class at the time.
The Altima Coupe was introduced in 2007. It is shorter and smaller and comes with 2 doors. The Altima Hybrid Electric was also a first for Nissan in the 2007 model year. It gets about 34 miles per gallon, but is also sportier than most hybrid cars.
The Altima can be bought new at a dealership, but for a much better deal I suggest you buy a used Altima on eBay, along with all the parts you'll need to make it run well and fast.