Set Flags shows how to store multiple boolean flags in a single integer value. In programming, this is known as a bitmask or as bit flags, and the idea is based on the binary number system where each digit can be only 0 or 1 (on or off, true or false).

For example, in the binary number 1010, you have four bit flags: flags 0 and 3 are false, and flags 1 and 4 are true. The decimal equivalent of 1010 is 10 (2¹ + 2³).