Grid and Snap
SolidWorks snaps to sketch geometry on the fly. For example, as the pointer approaches a line endpoint, the pointer changes to recognize the endpoint so you can choose to select it.
SolidWorks offers a display grid and snap grid while in sketch mode and in drawings. You can align the grid to a model edge and you can snap to an angle. The grid and snap capabilities are not often used in SolidWorks since dimensions and relations provide the required accuracy.
Grid with snap in a sketch
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Grid aligned to a specified model edge
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Related SolidWorks Topics
Align Grid/Origin PropertyManager
Grid and Snap Options