# Change Column
In this document, you explore how to make changes to a column in Astera Dataprep.
1. To change a column, select the *Layout* option in the toolbar and select *Change Column* from the drop-down.
Alternatively, you can also right-click on the column you need to change and select the *Change Column* option from the drop-down.
2. Once selected, the *Recipe Configuration – Change Column* panel will open. Here, you can define the *Name, Operation,* and any related information depending on the *Operation* that you have selected.
* **Name:** The name of the column that needs to be modified.
* **Operation:** The modification that needs to be applied to the column. This drop-down consists of three options: DataType, Header, and Value.
* **DataType:** Select this if the column’s data type needs to be modified. If selected, you can use the Type drop-down to choose a new data type for the selected column.
* **Header:** Select this if a column’s header needs to be changed. If selected, you can specify a new header in the *Header* textbox.
* **Value:** Select this if you need to modify the value within a column. If selected, you can use the expression box to enter an expression that you want to be applied.
3. Once you are done with the necessary configurations, you can select the *Apply*  option for the changes to be applied to the selected column.
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