Engine oil pressure is below a minimum. Engine can seize, causing severe engine damage. It is NOT safe to drive. Stop driving immediately, switch off the engine and seek assistance!
Usual problems: oil level is low, worn or broken oil pump, excessive main bearing wear.
Oil’s main function is to lubricate moving parts in the engine. It also cleans, inhibits corrosion, improves sealing and cools the engine by carrying heat away. First, check the oil level, and if it is low, add oil to bring the level to the full mark. If oil level was low, it means your engine is either leaking oil or burning oil.