Most modern theatrical films are created in a shape that is different from the shape of a standard television set. A standard TV is 1.33 times as wide as it is tall; in other words, it has an aspect ratio of 1.33:1. Movies are much wider, with an aspect ratio of 1.85:1 or 2.35:1; hence the word widescreen. This leads to problems when attempting to watch a movie on TV. One solution is to use a modified aspect ratio (MAR), changing the shape of the film image to fit the TV screen. Common methods for presenting MAR are pan-and-scan and open-matte. The other solution is sometimes called letterboxing, in which the film is presented in its original aspect ratio (OAR) by shrinking the image so that its width matches the width of the TV screen, leaving extra space above and below.

This category contains sites related to the widescreen format, including explanations, comparisons between OAR and MAR, and advocacy.