Your computer cannot function without an operating system.  The operating system is the brain that makes the various hardware work together.  Computers have operating systems, but other electronics have them as well.  Cell phones, video game systems, and even TiVo have operating systems although they aren't as obvious as they are on a computer.
 
Many years ago, two enterprising young men realized that an operating system would make a computer more user friendly and run more smoothly.  Bill Gates and his team of programmers at Microsoft developed the first real operating system with MS-DOS.  But they weren't completely satisfied that this was the ultimate operating system.  MS-DOS relied on commands that a user had to input, and many people weren't able to adapt easily to the system.

A device driver or a software driver is a specific type of computer software typically developed to allow interaction with hardware devices such as a mouse or a printer.  This software causes an interface for communicating with the device through the specific computer "bus" or communication subsystem that the hardware is connected to.  The software provides commands to and receives data from the device and, on the other end, the requisite interfaces to the operating system and software applications.
 
In plain English, a device driver is a program that allows various hardware to work on your system.  The driver will allow your hardware to communicate with your operating system making the devices operable in the proper way.

Your computer's hardware is the physical part of the computer, not to be confused with software which is not physical.  Computer hardware includes the digital circuitry.  Computer hardware includes the central processing unit (CPU), the monitor, the keyboard, the mouse, and the printer as well as any other peripherals you want to add such as a scanner or a video camera.
 
The hardware of a computer is not very often changed as opposed to the software and data which can be changed all the time depending on user requirements.  Most computer hardware is not seen by the user.  In fact, there are many common household objects that contain hardware that is embedded in systems in automobiles, microwave ovens, and compact disc players.

Media player is a term typically used to describe computer software that can play back multimedia files like text, graphics, and animation.  Most software media players support an array of media formats including audio and video files.  Some media players focus only on audio or video and are known as audio players and video players respectively.  The producers of these players usually focus on providing a better user experience as they are specifically tailored toward the media type.
 
Although the term usually refers to computer software, the term is also used for the media playback devices used in digital signage.  The term may also be used to describe analog electrical or mechanical playing equipment such as a phonograph or player piano.

A network operating system is software that controls a network of computer and its message traffic and queues.  It controls access by multiple users to network resources such as files and provides for certain administrative functions including security of the system.  A network operating system is not the same as the networking tools provided by some existing operating systems such as Windows XP.  A network operating system is one that has been specifically written to keep networks running at optimal performance.
 
A network operating system is most frequently used with local area networks and wide area networks, but it can also have applications for larger network systems.

In general, the term open source refers to the principles and methodologies to promote open access to the production and design process for various goods, products, and resources.  The term is most commonly used in reference to source code of software that is made available to the general public with either relaxed or non-existent intellectual property restrictions.
 
Open source allows users to create user-generated software content through either incremental individual effort or through collaboration.  In layman's terms, open source means that software is made available to the general public for download.  People can then either work alone or with others to change the software, make it better, and re-distribute it.

A resource or system resource is any physical or virtual component of limited availability within a computer system.  Every device connected to a computer system is a resource as is every internal system component.  Virtual system resources include files, network connections, and memory areas.
 
The four major types of resources include:

* CPU Time - The time is takes for the central processing unit to interpret and executed instructions input into the machine.
* Random Access Memory - The storage unit in the computer's CPU

Computer software programs enable computers to perform specific tasks.  It is removable and is differentiated from the physical components of the computer system which is called hardware.  Application software allows a user to do something specific as in a word processing software program.  System software allows the computer to run application software by interfacing with hardware and other software made to user specifications.
 
In computers, software is loaded into the random access memory (RAM) and is executed in the central processing unit (CPU).  At its lowest level, software consists of machine language specific to an individual processor.  Software is a sequence of instructions that changes to state of the computer's hardware in a particular sequence so that the programs can run properly.