Size increases or decreases the size of the brush tip.On many of the presets, you can easily adjust two very important values: When you click on the Brush Preset Picker in the default Options Panel, you will see several built-in presets. The Brush Tip settings allow you to modify the way to add colors on a Photoshop document using the Brush Tool. This is the most basic option for the Paint Tool in Photoshop. Photoshop includes several built-in presets, which are premade brushes ready to use. You must understand those concepts before moving forward with the advanced settings. The essential options for the Paint Tool in Photoshop are Brush Tip Shape, Blending Mode, Opacity, and Flow.

The Brush Tool works by adding a shaped mark on a layer, and if you continue pressing the mouse button or the pen on a tablet, several marks will be added, creating a stroke, until you release the pressure. It's located in the standard toolbar, and its default shortcut is the letter B. It works like a traditional drawing tool by applying color using strokes. The Brush Tool is a primary painting tool.

Brush tool photoshop