# Expression keywords

The following keywords are used in Data Shaping Expression Language. They are case insensitive.

* [Assignment expressions](https://help.qlik.com/talend/en-US/data-shaping-language-reference-guide/8.0/assignment-expressions) keyword
  * let
* [If-Else expressions](https://help.qlik.com/talend/en-US/data-shaping-language-reference-guide/8.0/if-then-expressions) keywords
  * if
  * elseif
  * ```
    else if
    ```
  * else
  * ```
    then
    ```
* [Switch-Case expressions](https://help.qlik.com/talend/en-US/data-shaping-language-reference-guide/8.0/switch-case-expressions) keywords
  * switch
  * case
  * default
* [Logical expressions](https://help.qlik.com/talend/en-US/data-shaping-language-reference-guide/8.0/logical-expressions) keyword
  * not
* [Operator expressions](https://help.qlik.com/talend/en-US/data-shaping-language-reference-guide/8.0/operator-expressions)
  * between
  * and
  * in
  * and
  * or
* Literals
  * true
  * false
  * null

Information noteNote: These keywords cannot be used as identifiers.