There are 24 icon buttons on the tool panel, as well as various menus and checkboxes. The best way to learn their functions is to play with them for awhile, testing out what you can and cannot do, observing what the effect is on a specific construction in the Canvas. Icons depict the functionality of buttons. Sometimes the functionality is quite clear, other times it is harder to figure out, but icons serve as reminders to what buttons do.
The Create Panel: Use the Create panel to create basic geometric objects, select them, label them, and gain information about them. Each of the eight buttons within the Create panel is enabled all the time. For more details see the Create Panel help page.
The Construct Panel: Use the Construct panel to construct geometric objects which depend upon simpler objects. For example suppose that you have already constructed a segment (with the segment tool) and a point somewhere off the segment. Then, you could construct a perpendicular to the segment through the point by:
2) Clicking the "perpendicular" button in the Construct Panel. This button, as well as the "parallel" button, should be enabled (black rather than gray), since both of these constructions are valid once a linear object and a point are selected. After clicking the perpendicular button the desired perpendicular is constructed.
The Transform Panel: Use the Transform panel to perform transformations on geometric objects. Each transformation requires you to select the object to be transformed along with other information that is specific to that transformation. One can also define compound transformations that are built from simple transformations. For more information, see the Transform Panel help page.
The Color Panel: Use the Color panel to set the color of an
object in
the canvas. Select all objects that you desire to be
a particular color. Then click the mouse on the appropriate color
square in the Color panel. Colors can be altered in the Color
Panel. If you hold the control key down while clicking on a color
square, a dialog box will pop up, allowing you to change the color of
that square.