Binary is a bit confusing at first but once you've got your head around it it's fine.
The thing is, that the decimal number system (which is primarily used) is base 10, and goes from 0 through to 9; however binary is a base 2 number format so only uses 0's and 1's.
There's a link about how binary works here (see bottom of page):
http://www.calculator.net/binary-calculator.htmlAs for your courses, they look like good subjects to choose for those courses.
I take it you will be dropping History at the end of year 12? I don't personally see any problems with that; you can then take your other 3 to A2 level.
I dropped ICT at AS because it was recommended that, due to A2's being harder than AS's, that I'll need more time per subject - thus it wouldn't be a good idea to do all 4 subjects. ICT was interesting, but didn't really add anything to the university course I wanted to do (Physics or Chemistry).
Then went through clearing at the end of the A2 year and picked up the Electronic Engineering course
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