Do different cars need different coolant?
Moreover, does it matter what coolant you use?
Well, you use the coolant that is specified in your owner's manual. If you just need to top it up, the recommendation is still the same, however it is unlikely to cause any serious problems if you add a litre of a different type of coolant, as long as you follow the manufacturer's maintenance schedule.
Considering this, is there a specific coolant for cars?
There are three main types of coolant that car companies use: Inorganic Additive Technology (IAT), Organic Acid Technology (OAT), and Hybrid Organic Acid Technology (HOAT). Typically, older cars use IAT. They'll sell the coolant for your specific make and model, and it's guaranteed to be the correct one.
Mixing different engine coolants or using the wrong coolant can impair the performance of the special additive packages; this can result in increased corrosion to the radiator. Using the wrong engine coolant can gradually lead to corrosion and damage to the water pump, radiator, radiator hoses and cylinder gasket.