Similar to letterbox, but instead of having edge above and below content, there's edges on both sides of the content.

Where letterboxing can be artistic choise, pillarboxing is more often caused by technical issues. Most often caused by incorrect aspect ratio where non-widescreen content was rendered in widescreen or image being screencapped on mobile device instead of saving the image.

Not to be confused with bright red post box, pillar box, from england.

See also

• Border
• Letterbox
• mailbox