pxt-calliope/docs/reference/js/statements.md

# statements, operators, and libaries

Statements, operators, and libraries.

### @parent js/language
 

TouchDevelop functions include statements and operators.

### Statements

TouchDevelop statements include:

* [break](/js/break), to exit a loop before it has completed, usually used in conjunction with an [if](/reference/logic/if) statement
* [if](/reference/logic/if) conditional statement
* [for](/reference/loops/for) and [while](/js/while) loops
* [function](/js/function)
* [return](/js/return)
* [var](/reference/variables/var) (local variable declaration)

### Operators

TouchDevelop operators include:

* [assignment operator](/reference/variables/assign) `:=` (to update variables)
* arithmetic operators (`+`, `-`, `*`, `/`, mod) operate on [Numbers](/reference/types/number)
* comparison operators (such as `>`, `=`) operate on [Numbers](/reference/types/number)
* boolean operators (`not`, `or`, `and`) operate on [Booleans](/reference/types/boolean)
* concat operator combines [Strings](/reference/types/string)

### Libraries

Libraries provide additional functions:

* the [micro:bit library](/js/contents)
* the [math](/js/math) and [bits](/js/bits) libraries

### see also

[TouchDevelop Documentation](/js/contents), [comments](/js/comment)