The selection tools are used to facilitate the process of making selections of shapes, colors, and objects inside of Photoshop, and positioning them in the working image area. With tools like the magnetic lasso and magic wand, Photoshop packs a powerful array of selection gadgets!

In Photoshop, selections are used to work in a specified area, while not altering any of the area around it. In many regards, a selection is a lot like a stencil. You basically are enabling yourself to only paint in one area while the rest of your canvas is left unaffected.

There are a variety of tools to help you draw out specific sizes and shapes of selections in Photoshop.
Marquee Tools

The marquee tools are used to make rectangular, elliptical, horizontal and vertical line selections. To create a selection with a marquee tool, simple hold down your mouse button over the active image area, and drag out your shape.



Piece of cake!

Perfect Circle and Square Selections

When making selections with the Rectangular Marquee Tool or Elliptical Marquee Tool, itís possible to make perfect square and circular selections by holding shift when drawing our your selection.
Lasso Tools

The Lasso Selection Tools allow you to make selections of irregular shapes. Using the ordinary lasso tool, simply click and drag a freehand selection with your mouse. With the Polygonal Lasso Tool, click to make various points which will define a selection, and finish your selection by clicking the starting point.

The Magnetic Lasso Tool sort of combines the first two tools mentioned here. You click once, and begin to drag a freehand selection around the object you wish to select. The magnetic lasso tool tries to automatically create points itself while you follow the edge of your object (you can define points by clicking if needed). The end result is a much smoother selection than the polygonal lasso tool will make.





Now we have a general idea of how to make selections of various shapes in Photoshop. There is also a way to select objects and areas based on color.

Magic Wand Tool

The Magic Wand Tool is unlike the rest of the selection tools, in that is selects areas based on color. To use the Magic Wand Tool, you simply point and click the color you want to select in the active image area.

Take the diagram below for example. Using the Magic Wand Tool, it simply takes one click in the white area to make a selection of that space.



Hereís a tip that ought to come in handy! While using the Magic Wand Tool, itís possible to select a wider (or more narrow) range of colors when making your selection by adjusting the Tolerance value in the options bar. The higher the value, the more similar colors will be selected!
Combining Selections

Sometimes, itís necessary to combine multiple selections in order to select the ENTIRE area you want to work with. In times like these, itís possible to combine multiple selections using an easy keyboard shortcut.

Working from an existing selection, simply hold shift and create a new selection. This will add your new selection to the existing selection.



Subtracting and Intersecting Selections

Just like it is possible to add to an existing selection, you can also subtract from a selection (Hold Alt when drawing a new selection) and intersect selections (Hold Shift and Alt while drawing a new selection).
Move Tool

The Move Tool is used for moving selected areas of an image, layers, shapes, and other objects.
To move a selected part of an image, simply select the move tool, and then click and drag your selection as you please. This will Cut the selection out from itís current location, and reposition it to wherever you release the mouse button.



Essentially, moving a selected object is like cutting out a part of a painting, and then putting it somewhere else. Just like cutting something out from a painting, the area which was cutout will now show whatever is behind the canvas (in this case, the background color, or layer behind that area).

Crop Tool

The Crop Tool is used to resize the canvas and active image area. To use the crop tool, simply drag out a square that encompasses the area which you want to become the new canvas size.
Note that cropping an image will not delete layer data. All layer data is preserved when an image is cropped to be smaller in size. Some layer data may just not be visible since it might become outside of the active image area.