Firewall-
1.it is a system that is designed to prevent unauthorized access from entering a private network.
2. It creates a safety barrier between a private network and the public internet.
3. It is especially important to large organizations

Firewall rules can be based on
	IP addresses
	Domain Name(i.e.website name)
	Protocols
	Programs
	Ports
	Keywords

Firewall Types-
1. Network Based firewall-
		   (a) Combination of hardware and software
		   (b) protects an entire network
2. Host based firewall- (a) software firewall that is installed on a computer
		   (b) protects that computer only
		   (c) A lot of antivirus programs come with a host based firewall
	
firewall can be (1) stand-alone firewall(hardware firewall), 
	       (2) router have a built-in firewall(hardware firewall), 
	       (3) cloud firewall (software firewall)this is testing