Via: http://psd.tutsplus.com/tutorials/3d/create-a-spherical-3d-puzzle-with-photoshop/

Marquee Tool
The marquee tool selects areas within a layer. It is capable of selecting an elliptical, square, single column, and single rows.
Move Tool
The move tool can move around all objects within a layer. To move entire image, Flatten the layers by selecting Layer > Flatten Image.
Lasso Tool
The lasso tool can select areas within in a layer that can’t be reached with the marquee tool.
Magic Wand
The magic wand is an automatic selection tool. It selects everything in the layer.
Cropping tool
This tool changes the size of the image. To use, Select the area you want to crop and then press enter.
Slice Tool
Makes Guidelines.
Heal Brush Tool and Patch Tool
The patch tool is another form of the heal brush. It is in the options for the heal brush. The Heal Brush deletes the high contrast of a picture and is used when retouching a photo. To use, hold down alt while clicking on the source (an area that looks like what you want the damaged part to look like) and drag the mouse around the damaged picture to repair it.
The patch tool fixes damaged parts of a picture by blending the damaged part with a better one. Just use the patch tool to select part of the image, then drag the selection to another part of the image. This will combine the selections.
Pencil tool and brush tool
Draws or paints a line. Same as the pencil or brush tool in paint. Change the color of the paint brush by clicking on the color picker.
Clone Stamp Tool and Pattern Stamp tool
The clone stamp tool duplicates part of the image. Hold down alt while clicking to choose the part of the image which you want to duplicate. Drag the mouse over the damaged area.
The pattern stamp tool can create and save a pattern you want to use over and over again. To make a pattern, use the marquee tool or the lasso tool to select part of the image. Go to Filter > Pattern Maker and click generate. Click on the floppy disk underneath the Tile History called Save Preset Pattern. This will save the pattern. Do not push OK unless you want to fill the entire image with that pattern. Press cancel and select your pattern from Pattern on the top center of Photoshop. Drag the mouse over the area with the pattern stamp tool to edit the picture.
History Brush Tool and Art History Brush
The history Brush tool can go back and undo certain changes in a picture. To delete everything you did since the opening of the picture simply drag the history brush over the area to be repaired. The history brush works best when transforming snap shots. Using the snap shot will only change certain parts of the picture and can go back in editing to change major errors. To make a Snap Shot, save the picture then click on the small camera on the bottom of the history window. The snap shot will be saved once it is named. If you click on a previous snap shot, you can edit a previous version of your picture. Click on the last snap shot then use the history brush tool to undo the editing to make the unedited section look like the previous snap shot.
The Art history Brush tool can artistically undo an image and warp the original picture. Click on the top snap shot and chose what kind of brush to use on the top of the window under Style. Click on the area you want to edit with the art history brush.
Eraser tool
This can erase part of the photo in a certain layer. To erase everything in a certain area to make it white, flatten the image or go through every layer to delete that part.
Paint Bucket
Makes an area one color. To edit all layers at one time, click on All layers at the top of the window.
The Blur tool, Sharpen Tool, and Smudge Tool
To use, drag over part of photo you want to edit. The hardest part of this tool is selecting the right strength, brush size and mode. This tool is capable of blurring part of the image, undoing the blur with the sharpen tool, and slightly liquefying with the smudge tool.
The Dodge tool, Burn tool, and Sponge tool
To use any of these tools, just drag it over the image. The dodge tool can lighten an image, the burn tool darkens it, and the sponge tool soaks color out of the image.
Type tool
Puts text in a picture. Click on the picture with the type tool and select a box the size of the area you want to add text. Type in the box then adjust the size of the text box.
Pen Tool
The pen tool can make lines and be used with shape tools to create different shapes. To create lines, use the pen tool to create anchors (the little boxes on a line) and change the shape of the line by moving around the anchors.
Shape Tools
Creates shapes in the image. The custom shapes tools can create all shapes in the shape section located at the top center of the Photoshop window.
Annotation tool
This can create notes and sound effects in an image. The only difference between the note tool and the text tool is that the note comes up in a little white box and when the note is too long for the given space, there will be a scroll bar. This is usually used in PDF formats and Acrobat Documents.
The audio Annotation tool can add audio notation to the picture. To use, click on the audio notation tool and press start. Record your voice with the microphone then press stop. You can import the audio by File > Import > Annotations. Make sure the file you import is a PDF file or a FDF file.
Eyedropper tool
Samples a color from the picture, color swatches, or the color picker. To use, click on the color on the image you want to take and right click.
Hand Tool
Moves around image within an object. Is used with the zoom tool when you want to adjust the section of picture you want to look at.
Zoom tool
Zooms in on part of the picture for closer editing.