All technologies
This technique helps avoid situations where horizontal scrolling may occur. Many people with cognitive disabilities and low vision users who do not use assistive technology have a great deal of trouble with blocks of text that require horizontal scrolling. It involves not interfering with the reflow of text if the window is narrowed. One of the best ways to do this is to define widths of text block containers in percentages.
HTML user agents automatically reflow text as the browser window is narrowed as long as the author does not specify widths using absolute measurements such as pixels or points.
A newspaper site includes articles with columns that adjust with the user agents window width. Users with cognitive disabilities can narrow the column to a width that makes it easier to read.