Can someone help me with some air conditioning questions? (Details follow)

Questions regarding air conditioning systems…for a house that

A. is really old, but rather compact.
B. has only window units
C. is in a zone that is very hot/dry and hot for most of the year

1. Has any new technology (different window units, for example) been developed to cool a house?

2. What is the difference between a swamp/evaporative cooler and an air conditioner?

3. Which of the above would work best in a super hot Southwest climate?

4. Any other suggestions for cooling an old house that only has window units?

Thank you.