Essential things to remember from today's class (class 12, 28th September)

Understand why over-estimating the initial maximum value for integer sqaure
   root is dangerous (leading to incorrect answers) and under-estimating it
   means there will be valid square roots that we can't find.

The while loop, and how it can be useful even though we are still restricted
   to using constants. It seems as though the loop condition could never change,
   but a bool function makes it possible.

The basics of using Unix:

   logging in and out

   changing your password

   creating and editing a C++ program (or any other text file)

   compiling and running that program