Rulers and Guides
Rulers
Rulers are measuring tools that appear along the top and left side of the workspace to help in accurate placement and sizing of objects.
Features:
Show measurements in pixels, inches, cm, etc.
Help align images and elements precisely
Can change units as required
Shortcut: Press Ctrl + R to show/hide rulers
Guides
Guides are non-printing horizontal or vertical lines used to align objects on the page.
Features:
Drag from rulers to create guides
Help maintain proper alignment and layout
Can be moved, locked, or deleted
Do not appear in final output