Bash on its own only supports integer numbers, and often in surprising ways. That said, we can get a lot of mileage out of integers. We won’t look at every one of the 30+ arithmetic operators available in Bash — they are documented in the “Arithmetic Evaluation” section of
man bash — but we are going to look at how operators are used in practice. For tasks involving complex math, Bash is often the wrong language, but we’ll look briefly at an example at the end of the chapter.