Now that you’ve wrapped your mind around Paths , understanding the Shape  Tools should be simple.  A Photoshop  Shape is nothing more than a path that acts as a container for a fill.   It can be edited in exactly the same way as a Path  in that it also contains Lines Segments which are connected by Anchor Points which can be modified by adjusting Direction Lines.   Shapes can also be used to add or subtract from other Shapes or create entirely new Custom Shapes.  Shapes can also utilize any of the Layer  Styles  settings available in the Layers  Palette .

Let’s take a look at how Photoshop  handles Shapes by placing a single Rectangle in our Image Window .  Create a new document that’s 300 pixels wide by 300 pixels high and draw a rectangle using the Rectangle Tool .  Direct your attention to the Layers  Palette  and take note of the new Shape  Layer  that has been added to it.  Hold down the [ALT] key and {Double Click} on the Layer if you’d like to rename it.

A Shape Layer

A Shape  Layer  contains both a thumbnail of the Shape’s color and its location.   Notice that the Shape’s color is the current Foreground Color.  If you’d like to change the color simply {Double-Click} on the Color Thumbnail and use the Picker to select a new one.  If you’d like to add an additional Shape to the current one simply draw it in the Image Window  and it will be added to the current Shape Layer.  If you’d like to add a new Shape on a different Layer {Click} once on the Shape’s Location Thumbnail.  Notice that the white outline around the Location Thumbnail disappears.  Draw another Rectangle in your Image Window and you’ll find that a new Shape Layer has been added to your Layers  Palette .

{Click} on the Shape  Location Thumbnail on the original Rectangle’s Layer .  The white outline should reappear around the thumbnail indicating that any Shape we draw will be placed on that Shape Layer.  We’re going to create a composite Shape by adding more elements to our original rectangle.  Take a look at your Options  Bar to see what types of options are available to you.

Shape  Tool Options  Bar

The Options  Bar not only allows you to choose what type of Shapes you’d like to create but also how you’d like those Shapes to interact with each other. 

Combination Options  

Shapes on a single Layer  can be added to, subtracted from, intersected with, or excluded from other shapes.  All you need do is select the particular option that you require, draw your shape, and Photoshop  will do the rest for you.  Below you will find some examples of how the various options work using our original rectangle and an additional rectangle.

These are rather simplistic examples.  If you put your mind to it you can create some interesting designs using combinations of shapes.

Note that each of the components within your composite shape can be selected individually and modified.  Use the Path  Component Tool     if you want to select one whole shape on a Shape  Layer  or the Direct Selection Tool   if you want to edit Anchor Points within a single Path.

If you are happy with the way your composite Shape  looks you can combine the various elements that go into it and create one Shape.  Multiple select the various Shapes that make up your custom shape with the Path  Component Tool  and {Click} on the Combine Button  in the Options  Bar.  Your composite is now a single path.

Let’s take a look at some of the other Shape  Tools available.

Rounded Rectangle Tool 
The Rounded Rectangle Tool  allows you to create Rectangles with corners that are rounded to whatever degree you wish.  Input a value in the Radius field to control the degree of curvature.  This tool is especially useful for creating capsule shaped buttons for website navigation.  {Click} on the Shape  Tool drop down menu to access the Options  for the Tool. 

The Square option constrains the proportions of your object to an equal width and height.  Fixed Size will automatically create a rectangle with the dimensions inputted in the Width and Height Field.  Proportional forces the Rectangle dimensions to a ratio that you designate in the provided fields.  From Center forces the Rectangle’s point of origin to be its center as opposed to its left top corner.  Most of these options apply to the other Shape  Tools as well and all of the keyboard shortcuts for the above options are identical to those utilized when drawing a Rectangular or Elliptical Marquee .  If you’ve spent much time using an earlier version of Photoshop  you’re probably already used to the keyboard shortcuts.

Ellipse Tool
The Ellipse Tool  functions in a similar fashion to the Elliptical Marquee .   Use it to draw circular and elliptical shapes.

Polygon Tool
Use the Polygon Tool  to create Shapes with multiple sides of equal length.  {Click} on the Shape  Tool drop down menu on the Options  Bar to access the various options available.  Below are 4 modifications of the same shape.

Line Tool
The Line Tool  doesn’t actually draw Line Segment s.  Input a value of 5 in the pixel field in the Options  Bar, draw a Line in your Image Window , and select it with your Direct Selection Tool.  The Anchor Points that appear indicate that the Line is actually a rectangular path that can be modified in exactly the same way as any other Shape  or Path .  Simply select the Anchor Points and modify them as you would any other shape.  Select the Tool’s drop down menu and you can add arrowheads of various sizes to either or both ends of your Line.

Custom Shape Tool
The Custom Shape Tool  allows you to place unique paths in your document.  Click on the Shape  drop down menu to see your options.

You can add your own Custom Shapes to the Menu  by first selecting the Shape  Layer  with the Shape or Shapes that you want to add and then navigating your way to Edit/Define Custom Shape from the Menu.