Software is a collection of instructions, data, and programs used to operate computers and perform specific tasks. It is the counterpart of hardware, which refers to the physical components of a computer. Software encompasses applications, scripts, and programs that run on devices, making it the variable part of a computer while hardware remains constant.
There are two main categories of software: application software and system software.
Application software serves specific purposes and performs tasks, while system software manages a computer's hardware and provides a platform for applications to run on.
Other types of software include programming software, which
equips developers with the necessary tools for writing code; middleware, which
acts as a mediator between system software and applications; and driver
software, which operates computer devices and peripherals.
In the past, software was tailored for specific computers
and sold together with the hardware it supported. In the 1980s, software
started being distributed on floppy disks, and later on CDs and DVDs. Nowadays,
most software is purchased and directly downloaded from the internet, either
from vendor websites or application service provider websites.
The most common types of software include application
software and system software. Application software is a package of computer
programs that fulfill specific user needs or perform tasks. It can be
self-contained or consist of multiple programs working together. Examples of
application software include office suites, graphics software, databases, web
browsers, word processors, software development tools, image editors, and
communication platforms.
System software, on the other hand, runs a computer's
application programs and manages the hardware. It coordinates the functions of
the hardware and software, controlling the operations of the computer and
providing an environment for other types of software to operate. The operating system (OS) is a prime example of system software.
Driver software, also known as device drivers, falls under
the category of system software. It controls computer devices and peripherals,
enabling them to perform their specific functions. Every connected device
requires at least one device driver to operate properly, ranging from
nonstandard hardware like game controllers to standard hardware like USB
storage devices, keyboards, headphones, and printers.
Middleware is software that facilitates communication
between application and system software or different types of application
software. For instance, it enables Microsoft Windows to interact with programs
like Excel and Word. Middleware is also used to send work requests between
applications running on computers with different operating systems, as well as
to enable compatibility between newer and legacy applications.
Programming software and programming tools are utilized by
computer programmers to write code. They provide the necessary resources for
developers to develop, write, test, and debug software programs. Examples of
programming software include assemblers, compilers, debuggers, and
interpreters.
Software can be categorized into two types: application
software and system software. Application software consists of programs that
perform specific functions for end users, such as report writing and web
browsing. These applications rely on the computer's operating system and other supporting
system software to function. They are installed on a user's computer, utilize
its memory, and do not require an internet connection to operate. Web
applications, on the other hand, solely require internet access and can be
launched from devices with web browsers.
System software acts as an intermediary between computer
hardware and application software. It operates in the background and handles
the fundamental functions of the computer. Users do not directly interact with
system software, but it enables high-level application software to run
smoothly. System software starts executing when a computer boots up and
continues to run as long as the system remains on.
The software development lifecycle is a framework used by
project managers to describe the stages and tasks involved in designing
software. The process begins with planning and analyzing user needs, followed
by designing and implementing the software. Testing and maintenance ensure that
the software functions properly and remains operational.
Software design encompasses the structure of the software,
including data models, system component interfaces, and algorithms. It involves
architectural design, which outlines the overall system structure, high-level
design, which details the system's modules and functions, and detailed design,
which covers the implementation specifics.
Software quality is measured by its ability to meet
functional and nonfunctional requirements. Functional requirements pertain to
what the software should do, while nonfunctional requirements focus on how the
system should operate. Software testing is essential for detecting and
resolving technical issues within the code and ensuring the software's
usability, performance, security, and compatibility.
Software quality is determined by various characteristics,
including accessibility, compatibility, efficiency, functionality,
installability, localization, maintainability, performance, portability,
reliability, scalability, security, testability, and usability. These dimensions
assess the software's ability to perform its intended functions, operate under
specific conditions, and meet user requirements.
Overall, software plays a crucial role in computer
operations, executing tasks, and meeting user needs. Its different categories
and types cater to various purposes and enable the smooth functioning of
computers and devices.
A software license is a legally enforceable agreement that
imposes limitations on the utilization and dissemination of software. It grants
users the right to use the software without violating copyright and outlines
the responsibilities of the parties involved. The license may impose
limitations on how the software can be used and typically includes terms and
conditions such as fair use, liability limitations, warranties, disclaimers,
and protections for intellectual property rights.Software licenses can be for
proprietary software, which remains the property of the creator, or for free
software, where users have the freedom to run, study, change, and distribute
the software. Open source software is a type of free software that is developed
collaboratively, with its source code freely available. Users of open source
software have similar rights as those of free software.
In recent years, software vendors have shifted from selling
one-time licenses to a subscription-based model known as software-as-a-service
(SaaS). This model involves hosting the software in the cloud and providing
access to customers through a subscription fee, allowing them to use the
software over the internet.
While copyright protects against direct copying of code, it
does not prevent independent development of similar software. On the other
hand, a patent enables developers to prevent others from using the functional
aspects of their software, even if developed independently.
The history of software dates back to the late 1950s when
programming software was not readily available. Users had to write their own
software, mainly scientists and large enterprises. The timeline of software
history includes milestones such as the creation of the first software for the
Manchester Baby computer in 1948, the introduction of floppy disks in the early
1950s, the release of the Unix OS in 1971, and the launch of the free software
movement in 1983.
Throughout the years, advancements such as the release of
Mac OS, Microsoft Windows, and the development of key software applications
have shaped the software industry. The introduction of CD-ROMs, DVDs, and the
rise of cloud computing have also influenced the distribution and delivery of
software. Currently, the internet and the cloud have become the primary
platforms for software distribution, with subscription-based models and SaaS
becoming increasingly common. The advent of mobile applications and the shift
from physical media to digital downloads have further transformed the software
landscape.