Layers are used to group information in a drawing by function and to enforce linetype, color, and other standards.
Layers are the equivalent of the overlays used in paper-based drafting. Layers are the primary organizational tool used in drawing. Use layers to group information by function and to enforce linetype, color, and other standards.
By creating layers, you can associate similar types of objects by assigning them to the same layer. For example, you can put construction lines, text, dimensions, and title blocks on separate layers. You can then control the following:
Whether objects on a layer are visible or dimmed in any viewports
Whether and how objects are plotted
What color is assigned to all objects on a layer
What default linetype and lineweight are assigned to all objects on a layer
Whether objects on a layer can be modified
Whether objects display with different layer properties in individual layout viewports
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