What Does Driver Do? (© All Computer Studies)

A driver is a specially written program which understands the operation of the device it interfaces to, such as a hard disk, video card, sound card or DVD ROM drive. It convert commands from the operating system or user into commands understood by the component computer part it interfaces with. It also translates responses from the component computer part back to responses that can be understood by the operating system, application program, or user. The below diagram gives a graphical depiction of the interfaces between the operating system and the computer component.
What Does Driver Do? (© All Computer Studies)

What Is Application? (© All Computer Studies)

Applications are programs that are install in different operating system. On computers to give users the ability to do specific tasks. For Example, Microsoft Word 2013® is a software that gives the user the ability to write/read documents. Some program packages come in a set with multiple programs included to provide multiple capabilities such as the Microsoft Office 2013® suite of programs. This suite of programs also includes Microsoft Outlook 2013® which is used to send and receive E-mail. It also includes other programs with more capabilities.

How Application Programs Work

Application programs are written in a text based computer language. Once written, they are compiled into a binary (0101) language the computer understands. The application programs use function calls (as described in the section about operating systems) to interface to the various computer peripherals such as your keyboard, mouse, scanner, printers, and other devices. Most of these function calls are provided by the operating system so the application programs are usually compiled for a specific operating system such as Microsoft Windows XP ®, Microsoft Windows 7®, or Microsoft Windows 8®.