Lower third

In the television industry, a lower third is a graphic placed in the title-safe lower area of the screen

though not necessarily the entire lower third of it, as the name suggests.
Lower thirds are most commonly found in television news production, although they also appear in documentaries and even have begun to make appearances in amateur videos thanks to home-video non-linear editing systems (NLE).
In its simplest form, a lower third can just be text overlying the video. Frequently this text is white with a drop shadow to make the words easier to read. A lower third can also contain graphical elements such as boxes, images or shading. Some lower thirds have animated backgrounds and text.
Lower thirds can be created using basic home-video editing software or professional-level equipment. This equipment makes use of video's alpha channel to determine what parts of the graphic or text should be transparent, allowing the video in the background to show through.