There are several categories of small cars. Small cars basically consist of vehicles that are smaller than a truck, SUV, or minivan. They are sedans, compact cars, electric cars, or basically anything small and condensed. It all depends on what kind of vehicle that you may be looking to purchase.
A sedan is generally a small vehicle that seats approximately 5 passengers. There are generally 5 seatbelts, but it can get a little crowded to try and cram 5 adults into a sedan. They can be 2-door or 4-door vehicles and vary in size. They are lower to the ground, but not 2-passenger and sporty.
A compact is basically the step above a subcompact car, but the step below the mid-size vehicle. It is a condensed size that allows the vehicle to get excellent gas mileage. The vehicles are generally much less expensive unless you are purchasing hybrids or electric cars.
This is the cross between a regular gas fueled vehicle and an electric vehicle. The vehicle charges when it is running on gas, so that when fully charged you vehicle can run on the battery. This can help to increase the mileage that you receive from the vehicle. It is much more environmentally friendly vehicle that minimizes the pollution.
Electric vehicles are still in the new stages of development. There are several varieties that are available, but they are generally only available for traveling short distances. The vehicle can be charged at a charging station or even through your average outlet, but the outlet will take much longer.
There are a lot of options for the small cars, but they range in price depending on what you are looking to acquire. Compact cars tend to be the least expensive, then sedans, hybrids, and then electric cars. The list can change depending on the types of features that you choose to add-on to each vehicle. Certain vehicles will be limited on the amount of available features. The prices can go from extremely low to rather high depending on the make, model, and the amount of features.