Let's see an IPv6 address example:

2001:0ba0:01e0:d001:0000:0000:d0f0:0010

The address consists of 128 bits, versus the 32 bits of currently IPv4 addresses. It is represented as 8 groups of 16 bits each one, separated by the ":" character.

Each 16 bits group is represented by means of 4 hexadecimal ciphers, that is, each cipher has a value between 0 and 15 (0,1,2, ... a,b,c,d,e,f being a=10, b=11, etc to f=15).

An abbreviated format exists to designate IPv6 addresses when all endings are 0, for example:

2001:0ba0::

Is the abbreviated form of the following address:

2001:0ba0:0000:0000:0000:0000:0000:0000

The same way, an only 0 can be written, removing 0's in the left side and 4 0's in the middle of the address can be abbreviated (only once in each address), so:

2001:ba0:0:0:0:0::1234

Is the abbreviated form of the following address:

2001:0ba0:0000:0000:0000:0000:0000:1234

It also exists a method to designate groups of IP addresses or subnetworks that lies in specifying the number of bits that designate the subnetwork, beginning from left to right, using remaining bits to designate single equipments inside the network.

For example, the notation:

2001:0ba0:01a0::/48

Points that the part of the IP address used to represent the subnetwork has 48 bits. Since each hexadecimal cipher has 4 bits, this points that the used part to represent the subnetwork is formed by 12 ciphers, that is: "2001:0ba0:01a0". Remaining ciphers of the IP address would be used to represent nodes inside the network.