Wills even I'm struggling with this stuff. Been studying it all week and my mind is blown. Massive changes compared with IPv4 and a lot of frustration. I don't think I've been to bed before 3am all week!
Behind every website name you visit there is a unique number, or Internet Protocol address. The Internet currently works on version 4 (IPv4) of this numbering system, and allows for about 4 billion unique numbers (256*256*256*256).
Although in reality, only half of these are actually used up because of the way they're allocated to different companies, it's still staggering that there are that many electronic devices out there capable of all talking to each other.
To allow for more device to be added, version 6 was created, which allows for an almost unlimited amount of devices (16*16*16*16 * 16*16*16*16 * 16*16*16*16 * 16*16*16*16 * 16*16*16*16 * 16*16*16*16 * 16*16*16*16 * 16*16*16*16). Of course, there probably aren't enough numbers to give one to each of the stars in the universe!