In short a pink slip inspection report verifies your car is safe and ready for the road. It is required in New South Wales for your vehicle to be inspected, as a condition of registration renewal, if it is more than three years old.
They have now been renamed e-Safety Checks, which are sent to the RTA electronically.
If your vehicle PASSES a Pink Slip / e-Safety Check:
If your vehicle FAILS a Pink Slip / e-Safety Check: