Currently IP addresses are based on the version 4 of the internet protocol where there are 4 sets of numbers ranging from 0-255. For example (127.198.30.245).
IPv6 has a much larger address space where there are 8 sets ranging from 0000-FFFF. For example (2001:0db8:0000:0000:0000:0000:1428:57ab).
IPv6 also has protocol enhancements for security as well as many other features. IPv6 is not readily available from most internet service providers and is not widely used to date. This however will be changing in the coming years.
For more information on IPv6 please take a look at this
article.