HTML Applications or “HTA” is a Microsoft Windows program whose source code consists of HTML , Dynamic HTML , and one or more scripting languages which are supported by Internet Explorer, such as VBScript or JScript. An HTA executes without the constraints of the internet browser security model; in fact, it executes as a “fully trusted” application, and its usual file extension of an HTA is .hta.
To customize the appearance of an HTA, a new (optional) tag hta:application was introduced to the HEAD section. This tag exposes a set of attributes that enable control of border style, the program icon, etc., and provide information such as the argument (commandline) used to launch the HTA. Otherwise, an HTA has the same format as an HTML page.
Via Herve Le Duc