Posted by Amrita Gautam at May 15, 2021
There are several features of UNIX that have made it very popular. The main features of UNIX are as fellows:
UNIX is a Multi-user operating system which allows concurrent access to Host machine by multiple users working different terminals. In UNIX operating system, UNIX server allows multiple users to have access to the UNIX shell prompt at the some time. There can be three king of terminals can be attached to UNIX.
1. Dumb terminals:
It consists of a keyboard, Display device and no memory. There terminals are fully depending on central computer for their functioning.
2. Intelligent Terminals:
These terminals are also called as Microcomputer or any computer with disk and other peripherals like memory, processor etc.
3. Dial Up Terminals:
These terminals use telephone lines to connect with host machine. In UNIX not only computer is accessible but also all peripheral devices which are attached to it can be used by other terminals.
Another feature of UNIX is that it is a Multitasking operating system, because a single user can carry our more then one task at the some time .e .g .user can work on typing in editor as well as he can take printouts also. It provide foreground and background environment to carry out multiple task. For example user can do typing in foreground and printing in Background. It is usually done by dividing time interval between all program running in memory. These time slots are allotted by the operating system according to the priority of process. Figure 1.5 shows multitasking environment of UNIX.
open source Code
The source code of the UNIX system is not just executable code, which had been made available to users and programmers for their suggestions. Because of this, many people have been able to adapt the UNIX system in different ways .This openness had led to the introduction of a wide range of new features and versions. It had been easy for developers to UNIX, because the computer code for UNIX system is straightforward, modular and compact.
One of the main reasons for UNIX popularity is that UNIX is far easier to almost any computer with minimum hardware requirement in comparison to other operating systems. Portability is possible in UNIX because most of the UNIX operating systems are written in C language and C language programs are easily moved from one hardware environment to another.
Communication / Self Networking
At the time of UNIX designing it was one of the main objective that one user can interact with each other and share data with each other. However the networking feature was not available in the operating system at the start. This feature was added after the split between BSD UNIX and AT&T UNIX.
Networking allows users at one location to logon into other system at other sites. Once user gains access to remote system he / she can use resources and data of remote system normally as own resources. Accessing of remote system is possible to the permissions assigned to the user.
UNIX allows sharing of data but with predetermined permissions, so that no unauthorised user can access the system and data. UNIX system has various types of security at different levels of working like it has login and password facility. Without an authorised login and proper password one can not work with the operating system, similarly while working with operating system user can protect its data by assigning different types of permissions to files and directories.
Organized File System
UNIX is multi-user operating system and as the number of users increases disk capacity also increases. It is not unusual to have thousands or more files in the disk, UNIX provides organised hierarchical file system to manage all file in the disk.
UNIX is unique in its modular design, which allows users to add or remove modules to fit their precise needs. If a part or module is not needed, it can be removed or replaced by another module without impairing the operation of the rest of the system. This feature is especially useful in microcomputer with limited disk drive capacity.
UNIX Utilites and Software Development Tools
Over two hundred utilities are available in UNIX for function like sorting data, processing text, searching for information etc. These are powerful collection of tool that can be used to accomplish many tasks without writing new programs.A UNIX System consists of various tools that help the programmers to develop different application. These include the C computer; file processing,syntax analyser, version control System, library management utility,source code debugger, macro processor etc.
1.8 UNIX ENVIRONMENT
UNIX is a Multi-user multitasking operating System designed to do text processing, communication and many other task that are expected from the operating System. It has three different computing environment: Personal Environment, Time-sharing Environment and Client/Server environment.
Although UNIX designed for Multi-user environment but many users are installing UNIX on their personal environment trend had started in 90’s when various multi-users operating System came into existence.
In a Time-Sharing environment, all the computing must be done by the Host machine called as central computer and terminals connected to host machine are called as dumb terminals. Therefore, this environment is also called as central processing environment. In this environment central computer allot a time slice to each process attach to it according to the priority and execute processes accordingly. Because all the processes are executed by the central computer therefore, sometimes computer become so busy that the users becomes frustrated and helpless.