These are decimal numbers, and dots above some of the digits make them recurring decimals. One dot means the digit under it repeats infinitely. In other words, it goes on forever (and ever and ever).

A decimal number is any number made up of the digits 0 to 9. This can include whole numbers and numbers less than 1. You can use a decimal point to show which digits are whole numbers and which are ...

When anyone is first introduced to the topic of digital computers, they are almost invariably told that these machines are based on binary (base-2) logic and the binary number system, where “binary” ...