Option bar

 Option bar

The options bar is positioned just below the menu bar. It is directly related to the tool, we selected. Whenever we choose a tool, this bar shows different options related to that tool that's why it is called an option bar. It displays context-sensitive settings and options related to the selected tool. The options bar changes as you switch between different tools. Most of the tools available in Photoshop can be customized as per the requirement and you can find all the options to customize a tool on the options bar once the tool is selected.  It allows you to modify and customize tool parameters such as brush size, opacity, and blending mode. 

 For example, if you're using the Brush tool, you'll be able to change the brush size, brush tip, and much more.