They are typically used to reinforce the vehicle and ensure that the passenger is protected in the event of an accident particularly if the car rolls.
													
																	Building a roll cage 101. 
									
	
		
	
																	A roll cage is a metal framework that can be built around the inside of a vehicle. 
																	Shown here is a visual difference between your basic 4 point roll cage and an 8 point roll cage from the chris alston s chassisworks catalog. 
																	Adding diagonal main hoop support braces turns it into and 8 point roll bar. 
																	Then you build upon that by adding bars for an 8 point roll cage then progress to an 8 50 or 10 point roll cage. 
															
													
									
	
		
	
																	The bars shown in blue are optional. 
																	A standard feature in race.