Three constituent countries of the UK lie in Great Britain:
Great Britain is the United Kingdom without Northern Ireland or the other islands, such as the Isle of Man. Great Britain is more liberal than Northern Ireland because the British don’t do nasty things to each other just because one is a Roman Catholic and the other is a Protestant. 
Not all Great Britain is liberal, the BNP and the National Front sadly still exist though most British people despise both.
- Historically especially before the 19th Century Great Britain was intolerant but today Northern Ireland has bigger troubles.