Internal hardware devices include motherboards, hard drives, and RAM.

External hardware devices include monitors, keyboards, mice, printers, and scanners.

The internal hardware parts of a computer are often referred to as components, while 

external hardware devices are usually called peripherals.

Together, they all fall under the category of computer hardware.

Software, on the other hand, consists of the programs and applications that run on

computers.

Because software runs on computer hardware, software programs often have system

requirements that list the minimum hardware required for the software to run.

The design of a Von Neumann architecture is simpler than the more modern Harvard

architecture which is also a stored-program system but has one dedicated set of address

and data buses for reading data from and writing data to memory, and another set of 

address and data buses for fetching instructions.

software programs, applications, scripts, and instruction sets all fall under the category of

computer software. Therefore, installing new programs or applications on your computer is

synonymous with installing new software on your computer.

Software can be difficult to describe because it is "virtual," or not physical like computer hardware.

Instead, software consists of lines of code written by computer programmers that have been 

compiled into a computer program. Software programs are stored as binary data that is copied to

a computer'shard drive, when it is installed. Since software is virtual and does not take up any 

physical space, it is much easier (and often cheaper) to upgrade than computer hardware.

Software is a general term for the various kinds of programs used to operate computers and related 

devices.Software can be thought of as the variable part of a computer and hardware the invariable part.

Software is often divided into application software (programs that do work users are directly interested in) 

and system software (which includes operating systems and any program that supports application 

software). The term middleware is sometimes used to describe programming that mediates between 

application and system software or between two different kinds of application software (for example, 

sending a remote work request from an application in a computer that has one kind of operating system to 

an application in a computer with a different operating system).An additional and difficult-to-classify 

category of software is the utility, which is a small useful program with limited capability. Some utilities come

with operating systems. Like applications, utilities tend to be separately installable and capable of being 

used independently from the rest of the operating system.Software can be purchased or acquired

as shareware (usually intended for sale after a trial period), liteware (shareware with some capabilities 

disabled), freeware (free software but with copyright restrictions), public domain software (free with no 

restrictions), and open source (software where the source code is furnished and users agree not to limit the

distribution of improvements).

the hardware and allows otherprograms to run. It is comprised of system

software, or the fundamental files your computer needs to boot up and

function. Every desktop computer, tablet, and smartphone includes an

operating system that provides basic functionality for the device.

Common desktop operating systems includeWindows, Mac OS X, and Linux.

While each OS is different, they all provide a graphical user interface, or GUI, 

that includes a desktop and the ability to manage files and folders. They also 

allow you to install and run programs written for the operating system. While 

Windows and Linux can be installed on standard PC hardware, Mac OS X can

only run on Macintosh computers. Therefore, the hardware you choose affects

what operating system(s) you can run.

Mobile devices, such as tablets and smartphones also include operating 

systems that provide a GUI and can run applications. Common mobile OSes 

include Android, iOS, and Windows Phone. These OSes are developed 

specifically for portable devices and therefore are designed aroundtouchscreen input. While early mobile operating systems lacked many

features found in desktop OSes, they now include advanced capabilities, such

as the ability to run third-party apps and run multiple apps at once.When 

software developers create applications, they must be write and compile them 

for a specific operating system. This is because each OS communicates with the

hardware differently and has a specific application program interface, or API,

that the programmer must use. While many popular programs are crossplatform, meaning they have been developed for multiple OSes, some

are only available for a single operating system. Therefore, when choosing 

a computer, it is important to make sure the operating system supports the 

programs you want to run.

A virtual machine is also known as a guest.

1. System Virtual Machines: A system platform that supports the sharing of the host computer's physical resources between multiple virtual machines, each running with its own copy of the operating system. The virtualization technique is provided by a software layer known as a hypervisor, which can run either on bare hardware or on top of an operating system.
2. Process Virtual Machine: Designed to provide a platform-independent programming environment that masks the information of the underlying hardware or operating system and allows program execution to take place in the same way on any given platform.