The main purpose of the colour palette is let you select precisely what foreground or background colour you need for the task at hand. 

 

You can always use the colour tools (overlapping squares) near the bottom of the toolbox to select, switch, or reset foreground and background colour, but the colour palette will give you a lot more options and precision for selecting colour.

You can specify a foreground colour by clicking the foreground square (the top overlapping square at the left of the palette) and then clicking a spot on the horizontal colour bar at the bottom of the palette. To choose a background colour, click the square that has its upper left corner underneath the foreground square, and then click a point of your choice on the horizontal colour bar.

 

If you happen to know the RGB values for the colour you want, you can enter them directly in the boxes at the right of the R, G, and B slider switches. You can slide RGB slider switches with your mouse to adjust the levels of red green and blue, and see the results immediately in the selected foreground or background box. 

 

With experimentation, you may notice that there are certain configurations of the R, G, and B colour components that reveal a small colour box with an exclamation mark in a triangle next to it. You can see this box and exclamation mark in the image at the right. This exclamation mark means that this particular colour is not possible in CMYK mode. In other words, cyan, magenta, yellow, and black pigments or inks cannot be mixed in any proportions that will yield this colour. This means that your printer will not be able to produce this colour exactly. The nearest colour that can be printed is shown in the small square next to the exclamation triangle. To choose this colour, click the triangle.

 

 

If you click the menu arrow in the upper right of the palette, you will display options for what type of colour sliders will be shown and what kind of colour spectrum (the horizontal colour bar along the bottom) will be shown.

The swatches palette is used to store a set of colours that you may be using frequently. You can add a colour to the swatches palette by choosing one with the eyedropper tool, or by using the colour palette, and then clicking on an empty spot in the group of swatches squares in the swatches palette. A paint bucket will appear under your mouse pointer if a swatch can be placed in the spot you choose.

When you add a swatch, you will see the following colour swatch dialog.

 

 

Type a name for your new swatch, and click the OK button to enter it into the swatches palette. If you let your mouse pointer hover over the new swatch, its name will appear in a small comment box. You can remove a swatch by dragging and dropping it on the trash can in the lower right corner of the palette.

 

If you expose the palette menu by clicking the right pointing arrow in the upper right of the palette, you will reveal a large number of options. If you choose the Reset swatches item from the menu, the swatches palette will be reset to its default arrangement.

 

The Styles palette is used to store and organize groups of effects (styles) that you can use on your images.

 

 

In Photoshop, images can be composed of multiple layers. You can select a layer from an image, and then click on the style of your choice in the style palette to apply it to the selected layer. If you click on the style in the upper left of the styles palette (the square with a red diagonal line) any style currently applied to the layer will be removed. You can use the scroll bar to reveal more style options. Like the other palettes, clicking on the menu arrow in the upper right will reveal several configuration options for the palette.

 

If you don’t understand what layers or styles are, don’t worry. In a simplified sense, a style is just a group of effects that can be applied to a layer, and layers are a bit like transparent sheets containing image elements, that can be overlaid to compose an image.

 

The following graphic shows the eagle image from the Photoshop sample folder, with a Sepia tone style applied to it.