# tMap expression syntax

This article introduces the syntax to use in the Expression Builder, to help you understand and use the tMap component.

tMap is one of the core components of Talend Studio and is used very often in Jobs. The tMap component is primarily used for mapping input fields to output fields and transforming the input data in the Expression Builder of the corresponding output column.

The Expression Builder allows you to type in a mapping expression for each column in each output table. This article presents the following syntax examples:

* [Basic mapping](https://help.qlik.com/talend/en-US/components/8.0/tmap/basic-mapping)
* [Concatenating fields](https://help.qlik.com/talend/en-US/components/8.0/tmap/concatenating-fields)
* [Setting output column with a constant](https://help.qlik.com/talend/en-US/components/8.0/tmap/setting-output-column-with-constant)
* [Outputting blank values as null or fixed values](https://help.qlik.com/talend/en-US/components/8.0/tmap/outputting-blank-values-as-null-or-fixed-values)
* [Arithmetic operation](https://help.qlik.com/talend/en-US/components/8.0/tmap/arithmetic-operation)
* [Calling a Java class method](https://help.qlik.com/talend/en-US/components/8.0/tmap/calling-java-class-method)
* [Calling a Routine](https://help.qlik.com/talend/en-US/components/8.0/tmap/calling-talend-routine)
* [If/else statement](https://help.qlik.com/talend/en-US/components/8.0/tmap/if-else-statement)
* [Filter expressions](https://help.qlik.com/talend/en-US/components/8.0/tmap/filter-expressions)

### In this section

* [Basic mapping](https://help.qlik.com/talend/en-US/components/8.0/tmap/basic-mapping)
* [Concatenating fields](https://help.qlik.com/talend/en-US/components/8.0/tmap/concatenating-fields)
* [Setting output column with a constant](https://help.qlik.com/talend/en-US/components/8.0/tmap/setting-output-column-with-constant)
* [Outputting blank values as null or fixed values](https://help.qlik.com/talend/en-US/components/8.0/tmap/outputting-blank-values-as-null-or-fixed-values)
* [Arithmetic operation](https://help.qlik.com/talend/en-US/components/8.0/tmap/arithmetic-operation)
* [Calling a Java class method](https://help.qlik.com/talend/en-US/components/8.0/tmap/calling-java-class-method)
* [Calling a Talend Routine](https://help.qlik.com/talend/en-US/components/8.0/tmap/calling-talend-routine)
* [If/else statement](https://help.qlik.com/talend/en-US/components/8.0/tmap/if-else-statement)
* [Filter expressions](https://help.qlik.com/talend/en-US/components/8.0/tmap/filter-expressions)