Example values
As described in RFC 2606 and RFC 6761, a number of domains such as example.com and example.org are maintained for documentation purposes. Sometimes you also need to differentiate between a customer domain and your own application domain, so Cloudflare has also registered some domains for you to use.
Examples:
example.comexample.orgmyappexample.commycustomerexample.com
IANA also maintains more example domains documented here.
According to the Internet Engineering Task Force (IETF), there are specific IPv4 ranges used for documentation:
Examples:
192.0.2.0/24.198.51.100.0/24.203.0.113.0/24.
These IP addresses are reserved and will not take anyone to live origins.