The term Lateral Thinking, was coined by Edward de Bono in 1957 to refer to a method of problem solving that uses creative and indirect methods that are not immediately available to the process of more formalized logic. While most academic and practical problems can be solved through the direct application of math, physics or logic, some problems can also be solved by alternate means.
One entertaining example of this is about how a physics professor challenged his class to find 3 ways to use a barometer to find out how tall a building is:
Solution 1 - (the most conventional answer) was to measure air pressure at ground level and on the top floor and then do the math to calculate the height.
Solution 2 - was to tie a string to the barometer and lower it from the top floor and then measure the string.
Solution 3 was to take the barometer to the building manager or caretaker and say "I'll give you this barometer if you will tell me how tall the building is."
All three of these solutions used the barometer to get a legitimate answer, but two of these were not the conventional way to use it.