Both the pen tool and the freeform pen tool let you draw smooth-edged paths. I have never found the need to use either of these, and don't now much about them. 

Like many of the other tools, there are more than one here. Holding down the ALT key while selecting the tool will reveal the one underneath.

18 - SHAPE TOOL -

Selecting this tool and applying it to an image creates different shapes, such as star shapes, squares, and rectangles with rounded edges. These come in handy when filled with color and a beveled edge is applied. They make great forum and sig logos and buttons, and can be used to promote different events, show your support, or simply put your point across.

19 - NOTES/AUDIO TOOL -

This tool is used to insert either a text notation or an audio notation to an image file. Mainly used by photographic imagery professionals, this is another tool I am not too familiar with. 

This is the time when experimenting with the different tools and their functions comes in handy. 

20 - EYEDROPPER TOOL -

Use this tool when you want to "copy" an exact color in an image, in order to either use that color for text or to fill in a shape. Works great every time!

21 - HAND TOOL -

This little ditty helps when you have an image on your workspace that is way too big to display all at once. By selecting the hand tool and then applying it to the image, you can easily "move" the image around the workspace for viewing. This is useful when working "close-up", but if not careful it can give you a sort of distorted view of your image. That is where the next tool comes in handy.

22 - ZOOM TOOL - 

This tool lets you zoom out or zoom in on your image. Selecting this tool and then applying it to the image will bring it closer (make it appear larger) to you. It does not, however, actually change the size or the shape of the image. 

Using the ALT key with the zoom tool while applying the tool to the image will zoom out, making the image appear as though smaller. 

You can vary the degree of zooming by right clicking over the image while the zoom tool is selected. This opens a small zoom menu that lets you choose in which state you want the image to appear, either print size, actual pixels, or fit on the screen. It's your choice. 

COLOR SELECTORS -

I purposely didn't number these, because they are in a class by themselves. 

Near the bottom of the tools palette are 2 colored squares, the default setting of which are black and white. These are the default colors, and will usually appear there unless other colors have been selected.

The black is by default the foreground color; where white by default is the background color. 

To change the foreground color to a different one, simply click on the black square. This opens up the color picker/selector, where you can then choose from a variety of standard or custom colors.

To change the background color, click the tiny arrows above and to the right of the colored boxes. This will "switch" the foreground color to white, and the background to black. Next, click on the foreground color (white) to open the color picker/selector. Make your choice and then click OK. 

You'll now notice the white has color has been replaced by whatever color you chose from the color selector. To switch that color to the background again, simply click on the tiny arrows once more. 

Always remember when working with color that the color of the box in front is the color you will be using. This applies to text as well, but only on the initial procedure.

When working with text, once the initial type is written on the image, you can then change the color to a different one by selecting the text tool, then selecting the text itself. At the top of the main toolbar you will see a tiny box that shows the current text color. To change this color, click the box of color and make your new color selection from the color picker/selector.