When creating or sizing objects, you can define points by entering them directly into the Coordinate Fields. By default, this toolbar is located at the lower right corner of the screen.
When moving the cursor, the values in the fields update dynamically.
The type of coordinates depends on the coordinate system you are using. In the absolute and relative coordinate systems you use X, Y coordinates. In the polar coordinate system you enter an angle and distance. See Coordinate Systems.
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If you enter a value and press Enter, Any Ortho or snap modes are ignored. You can also enter the results of mathematic mathematical expressions from the Calculator. See Calculator Palette - Variables Palette and Calculator Palette - Variables.
Locking: You can lock a coordinate by clicking the lock box. This means that no matter where you place the cursor, the value will remain fixed. 
You can also lock coordinates by using the Lock options in the Modes menu.
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The Coordinate Field also provides access to snap modes. Disable the SNAP button to temporarily turn off any running snaps, and disable the GEO button to temporarily turn off any running geometric aids Right-clicking on either the SNAP or GEO fields opens the Drawing Aids window. See Snaps.
