CNAME records are the indirection pointers of DNS. Instead of pinning an A record to a specific IP, a CNAME delegates resolution to another name whose owner controls the underlying addresses — a critical pattern for pointing `www.mydomain.com` at `mydomain.shopify.com` or `shorten.mybrand.com` at a URL-shortener provider's host. Three rules matter. First, a CNAME cannot coexist with other records at the same name; a name that has a CNAME must have only the CNAME and nothing else (no MX, no TXT) — this is why the zone apex (`example.com` without `www.`) cannot have a CNAME in standard DNS, a limitation many DNS providers work around with `ALIAS` or `ANAME` records that synthesize CNAME-like behavior at the apex. Second, CNAME chains add latency because each hop requires another resolver step. Third, because CNAMEs hand off control, changes at the target propagate without any edit on the source zone — useful for managed services that rotate IPs, risky if the target is ever hijacked or expires.