Enums are available only in TypeScript. On a few occasions, you may simply want to store a set of numbers, serially or not. Enums hand you a numeric data structure control without having to drag in the complexities of arrays or objects.

The following example shows an enum type with numbers from 0 to 2:

enum Status {Started, InProgress, Completed}let status:Status = Status.InProgress // 1

Enums are 0-based; therefore, Started holds 0, InProgress holds 1, and Completed holds 2. In addition, enums are flexible; hence, you can provide a number for the starting point instead of 0:

enum Status {Started = 1, InProgress, Completed}let status:Status = Status.InProgress // 2

You can write more expressive code with Enums. Let's see how, by using ...

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