Physics and Technology – Technology – Operating Systems
The software that makes the use of a computer possible is called the operating system. It manages and controls the running of the computer-from starting and ending the programs to managing attached devices.
Computers can only perform the functions for which they are programmed. Programs are written in languages that use logic and formal commands, often based on mathematical functions composed of algorithms.
Some common functions include logical sequences of events and their consequences, conditional queries, processing the size and position of objects, and access to external hardware like the hard disk or the Internet.
Assembler, interpreter, and programming languages
A processor receives instructions for computing and assigning memory space in an assembly language. These languages are easy to learn and are translated into computer code via the assembler software.
A disadvantage is that every type of processor requires its own assembly language. All types of processors, however, can execute high-level programming languages. Compiler software translates these programs into assembly language.
High-level programming languages
High-level languages are primarily used in application programs. General-purpose languages are used for a variety of applications; domain-specific languages are suited for special applications only.
Declarative languages define conditions to be satisfied by the program, and object-oriented languages execute commands for virtual objects. A few innovative languages do not use text commands. Instead, their functions are activated by mouse-clicking symbols displayed on the screen.
Examples of languages
C++ is a popular high-level language used for object-oriented programming, databases, and back-end applications. The JavaScript language expands the scope of possibilities on the Internet. It can run programs that detect the user’s hardware and adjust the display to be compatible with this hardware.
JavaScript is distinct from Java, another object-oriented language used to make applets for Web pages. HTML (Hypertext Markup Language) is not a programming language, but rather one for formatting Web pages. Hypertext Preprocessor (PHP) is an increasingly popular language used to implement dynamic Web sites.
OPERATING SYSTEMS
Linux is an open source operating system, meaning the user has access to the source code in which programs are written. The user can modify it or write additional programs that can be appended to it. Linux programs are distributed free of cost. Firms and private users are increasingly deciding to use open source systems.
Microsoft: Windows is the most used operating system in the world. It was introduced to the market in 1985 and its source code remains proprietary to this day.
Mac OS: X is a Unix-based operating system that is extremely easy to use. It is more stable than Windows, and particularly popular in creative professions.
BASICS
“TROJANS”—recalling the Greek myth—are seemingly harmless pieces of software that unload hidden programs to breach or even damage a user’s computer system.
SPYWARE programs gam unauthorized access to personal data, passwords, and code words.
DIALER programs link the user to expensive dial-up numbers—without the consent of the user.