Government
Whilst it is firmly part of Britain, Scotland is actually quite different in many aspects of its government. The legal system is separate for example, and the Scottish parliament now controls many domestic issues in the country such as healthcare and education. Because these differences are quite small, and do not generally affect visitors too much, you may not notice them while you are here. If you are quite familiar with England and Wales however it is best not to assume that everything you know will necessarily apply in Scotland as well
Culture and religious attitudes
Religion.
Scotland is traditionally more religious than the rest of the UK, with a large proportion of the population declaring themselves to be Catholic, Church of Scotland or Free Presbyterian. Football and schooling are often divided on sectarian lines as a result. You may see displays of religious pride (or more often religious intolerance), particularly on the west coast. Very occasionally this actually leads to violence, though this is almost always related to football, and is most easily avoided by not wearing team colours. Aside from this sectarianism, and certain Scottish islands which have strong views about alcohol and working on Sundays, religion seems to have very little effect on life in general in Scotland. Certainly it is more important to consider religious convictions in Spain or Poland than in Scotland.
National Pride.
Scotland has spent virtually its entire history in the shadow of Scotland. Almost inevitably as a smaller nation they have less success in sporting events, and in spite of recent moves to devolution political control still essentially rests with the English. Scottish people know this, but that does not mean that they are happy about it. It is not wise to suggest to Scottish people that Scotland is in any way inferior to England, or not a country in its own right.