Just letting you know, the other two answers are rubbish. Firstly, what are you doing with the laptop? Because remember that the Air only has 128gb or 256gb internal space, whereas the 15" pro has 500gb or 750gb (but is solid state vs hard disk).
The Air has a higher res screen/size ratio with a res of 1440x900, and the Pro has the same, but on a 15" screen (less pixel dense). The RAM is the same. Both have backlit keyboards, and the same multitouch trackpad.
Remember that the Air does not have a disc drive, wheresas the 15" pro does. What is most important, though is the processor and graphics. The 13" Air has a 1.7ghz i5 DUAL core vs the 15" pro's 2.2ghz QUAD core, making it more that 2x faster.
The graphics in the 15" low end are quite bad (256mb GDDR5), but are still 2x that of the integrated intel HD 3000 in the Air. The graphics car in the high end 15" is a 1gb GDDR5 6750m, which is quite powerful and runs every game basically on high/very high settings. Keep in mind that if you are gaming, getting the high end 15" is a much better idea.
Without gaming, and doing simple word processing and bringing everywhere, the 13" Air is better. Doing a bit of everything, such as video and photo storage and editing, itunes, work and documents, watching movies etc., the 15" is a much better idea if you are spending lots of time on the computer.
Not sure what James means by built the same! Maybe they're the same quality! Anyway, The Air doesn't have a DVD/optical drive!
Smaller lighter! I read a rummer that the next 15" MackBook Pro will be more like the Air! Thinner lighter and no DVD/optical!
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.