- Address size moved from 32-bit (IPv4) to 128-bit (IPv6)
- Divided into eight groups of 4 HEX characters: 2001:0050:0000:0000:0000:0AB4:1E3B:98AA
- Rule 1: Eliminate groups of consecutive zeros: 2001:0050::0AB4:1E2B:98AA
- Rule 2: Drop leading zeros 2001:50::AB4:1E2B:98AA
- Loopback address is ::1