a) The car engine turns well but does not start.
b) The engine itself does not turn or turns very slowly.
In case of (a) you need to check the engine, carburettor, ignition system etc.
In case of (b) if the weather is cold, the engine may take time to warm up. Be sure to check the grade of oil once. Or else, check your battery connection - in case of any problem, contact your nearest Exide dealer or Bat Mobile Service. Replace your vehicle battery, if it is faulty or recharge if it is low on charge and check fan belt and alternator output. Don't forget to test operating conditions. However, if battery function is smooth, check the starter motor and its connections.