Depending on what year car you have and brand. Look to see if it has coolant and oil in there respective storage areas. If it is full of oil and coolant thats a plus. If it turns over but won't start that is a good sign, depending on what it sounds like when it is cranking over.
If it does not crank over and it has a fully charged battery that may be terminal for the engine. Have a professional mechanic diagnose your problem just to be safe.