A title bar is the region on top of a computer window that displays basic information about what is contained inside that window. Title bars usually contain a brief description of the window's contents, as well as the name of the application from which the window came. Most windows in the graphical user interface of a computer have a title bar, and it is not very common to see a title bar blank, since appropriately descriptive title bars can tell a lot about a window.
Title bars are the small rectangular regions that span the very top of a computer window, and their descriptions are usually on the far left side. The descriptions may or may not be next to an icon designated by the program the window came from, but some kind of icon usually exists. Generally, the format of the description on the title bar is first a description of the window's contents, followed by some sort of separator, and then the program name. Main windows in a computer program are more likely to have detailed title bars, and small dialogs that sometimes pop up within a program are not always as detailed.
On the right or left side of the bar there are often buttons available for minimizing, maximizing, and closing the window. Like title bar descriptions, these buttons tend to be pared down depending on the type of window or dialog being shown. Main windows almost invariably have all three buttons, and some also have a help button nearby. Important dialogs usually have all three buttons as well, although the resizing buttons may absent or disabled if resizing is not necessary. Small message dialogs may have all three buttons, but they often have only a closing button, because resizing of messages is almost never necessary.
The exact look of a title bar varies, depending both on the application that opened it and the specific look and feel of a particular computer's desktop environment. While it is possible in programming to hard-code the look of a title bar, this is often discouraged because of the possibility that it clashes with a client's desktop environment. When programming, the bar's size, coloring, and general layout are usually taken care of by the operating system, so explicitly coding them is almost never necessary. As either a user or developer, paying attention to title bars can be crucial, both for purposes of information and comprehension, regardless of how it looks.