Device driver

Device driver are the software’s that act like “liaisons” between hardware in a computer system and OS. The operating system relies on device drivers to communicate with each device in the computer. A Device driver also called driver, is a small program that tells with each operating system how to communicate with a device. Each device of a computer, such as the mouse, keyboard, etc., has its own specialized set of commands and thus requires its own specific driver. When you boot a computer, the operating system loads each devices driver. These devices will not function without their correct drivers.
In the past, installing new hardware devices often required setting switches and other elements on the motherboard. Today, installation is easier because most devices and operating systems support Plug and Play. Plug and Play means the computer can recognize a new device and assist you in its installation by loading the necessary drivers automatically.

Utility Program:

Utility Program is a type of system software that performs a specific task, usually related to managing a computer, its devices or its programs. It is also called a utility. It helps in the management of computer hardware and application software. It performs small range of tasks. Disk defragmenters, system utilities, disk utilities, disk scanner, virus scanner are some of the typical examples of utility software.

Application software:

Application software utilizes the capacities of computer directly to a dedicated task. It is used to accomplish a specific task of computer. Application software programs have varied functional usages:
1. It is as productivity business tool.
2. It assists graphic and multimedia projects.
3. It supports household activities, personal business educational programs.
4. It facilitates communication tools.
A variety of application software is available as packaged software. You can purchase this software from relevant vendors in retails stores or on the web. Software that comes with a new computer system or devices, such as a printer, is called Bundled software.