# Perspective: Expressions - Column Selection

Column selection determines which data columns your chart will display and how they're used in the visualization.

## How Column Selection Works

- **Each chart acts on one or more columns**
- **First column**: Typically used for the X-axis
- **Second column**: 
  - If provided: Used for Y-axis
  - If not provided: Shows count of records

## Managing Columns

- **Add** - Include additional columns in your chart
- **Remove** - Delete columns you don't need
- **Reorder** - Change the sequence of columns

## Pro Tip

Include relevant columns in **Order By** to improve chart organization and readability.

## Visual Guide

![Column Selection Interface](./images/user/040__1.png)