In multi-column layouts, the column-rule CSS property specifies a straight line, or "rule", to be drawn between each column. It is a convenient shorthand to avoid setting each of the individual column-rule-* properties separately : column-rule-width, column-rule-style and column-rule-color.
The image-renderingCSS property provides a hint to the browser about the algorithm it should use to scale images. It applies to the element itself as well as any images supplied in other properties for the element. It has no effect on non-scaled images.
A media query consists of an optional media type and zero or more expressions that limit the style sheets' scope by using media features, such as width, height, and color. Media queries, added in CSS3, let the presentation of content be tailored to a specific range of output devices without having to change the content itself.