Types of Operating System

OPERATING SYSTEM

An operating system is the single most important software when you run a computer, it is what takes care of pretty much everything on a computer system, while the majority of computers we see happen to be using one ‘type’ of operating system performing the same functions, operating systems can be branched into several different types as well. It’s been a while since I’ve shared a fairly technical post on Computer Realm so I guess today would be a good day for one.

• Batch Processing Operating System

In a batch processing operating system interaction between the user and processor is limited or there is no interaction at all during the execution of work. Data and programs that need to be processed are bundled and collected as a ‘batch’ and executed together.

Batch processing operating systems are ideal in situations where:

- There are large amounts of data to be processed.

- Similar data needs to be processed.

- Similar processing is involved when executing the data.

The system is capable of identifying times when the processor is idle at which time ‘batches’ maybe processed. Processing is all performed automatically without any user intervention.

• Real-time Operating System

A real-time operating system processes inputs simultaneously, fast enough to affect the next input or process. Real-time systems are usually used to control complex systems that require a lot of processing like machinery and industrial systems.

• Single User Operating System

A single user OS as the name suggests is designed for one user to effectively use a computer at a time.

• Multi-Tasking Operating System

In this type of OS several applications maybe simultaneously loaded and used in the memory. While the processor handles only one application at a particular time it is capable of switching between the applications effectively to apparently simultaneously execute each application. This type of operating system is seen everywhere today and is the most common type of OS, the Windows operating system would be an example.

• Multi-User Operating System

This type of OS allows multiple users to simultaneously use the system, while here as well, the processor splits its resources and handles one user at a time, the speed and efficiency at which it does this makes it apparent that users are simultaneously using the system, some network systems utilize this kind of operating system.

• Distributed Operating System

In a distributed system, software and data maybe distributed around the system, programs and files maybe stored on different storage devices which are located in different geographical locations and maybe accessed from different computer terminals.

While we are mostly accustomed to seeing multi-tasking and multi-user operating systems, the other operating systems are usually used in companies and firms to power special systems.

Types of Printers

This article is to explain and detail the information about  types of printers. It is nothing but the output peripheral device which is used to produce hard copy of text or images stored in the computer. They are broadly categorised in to two types, they are
1. Impact Type
2. Non-Impact Type


Impact Type
To create text or image by physically make the print head to press the ink ribbon and  cause the ink deposition on the paper in desired form is called impact type. Normally it is quite louder in nature when compared to other  types of printers. The well known example for impact type is Dot Matrix and Daisy wheel . Some of the latest impact based in the market are Line printer (high speed impact printer), IBM electromagnetic table printing machine, and Apple Image writer.


Non-Impact Type
This  produce text or images on paper without striking the paper physically are called as non-impact type. These are not louder when compared to  other types of printers. The well known example of this type is Thermal printer, lasers and inkjets . Some of the latest non-impact printers in market are HP Laser Jet and Apple Laser Writer (The laser printer with built-in postscript interpreter).


Printing Technology
In overall, different printing technology is used for different level of printing. It is also classified on the basic of printing technology. The quality of printing, printing speed, cost of them are mainly based on the technology used .


Non-Impact Printing Technology
The technologies commonly used in modern and personal home based are non-impact type. These technologies can print in both mono chrome and colour. The following category can be classified under non-impact printing.
1. Tonner based (Laser)
2. Liquid ink(Inkjet)
3. Solid ink
4. Dye-sublimation
5. Thermal
6. Inkless
7. UV


Impact printing technology
Some of these devices are rarely used. They are famous for its unique feature, common use in businesses where multi-part forms are printed. These are mostly comes under the impact printers and they gets printed mostly in mono chrome only. following are different  types of printers in impact printing
1. Daisy wheel
2. Dot matrix
3. Pen based plotter
4. Line printer
5. Typewriter-derived
6. Teletypewriter-derived
These are mostly comes under impact printers. These are commonly used for commercial purpose for its special feature to print multi-part forms.

Simplify Explain by FIREWALLS

A firewall protects your network from unwanted Internet traffic. The primary functions of a firewall are to let good traffic pass through while ‘bad’ traffic gets blocked. The most important part of a firewall is its access control features that distinguish between good and bad traffic. 

When installed, a firewall exists between your computer(s) and the Internet. The firewall lets you request web pages, download files, chat, etc. while making sure other people on the internet can not access services on your computer like file or print sharing. Some firewalls are pieces of software that run on your computer. Other firewalls are built into hardware and protect your whole network from attacks.

Everyone connected to the Internet should be running some sort of firewall. Programs can be downloaded on the Internet that can scan huge ranges of IP address for vulnerabilities like file sharing services. These programs are easy to download and run. Almost no network knowledge is needed to use these programs to exploit or harm your computer. Any kind of firewall will keep you safe from these types of attacks.

Software Firewall

Software firewalls are programs that run on your computer and nestle themselves between your network card software drivers and your operating system. They intercept attacks before your operating system can even acknowledge them. Many free firewalls of this type exist on the Internet. Here are some free firewalls

Simple NAT firewall

The firewalls that are built into broadband routers and software like Microsoft ICS are very simple firewalls. They protect your LAN by not letting anyone figure out how to ‘directly’ talk to any of the computers on your LAN. This level of protection will keep out almost all kinds of hackers. Advanced hackers may be able to take advantage of certain inadequacies of NAT based firewalls, but they are few and far between.

Firewalls with stateful packet inspection

The new trend in home networking firewalls is called stateful packet inspection. This is an advanced form of firewall that examines each and every packet of data as it travels through the firewall. The firewall scans for problems in the packet that might be a symptom of a ‘denial of service’ (dos) attack or advanced attacks.

Most people are never subject to these types of attacks, but there are some areas of the Internet that invite these kinds of attacks. Most often, these attacks come from being involved in certain kinds of competitive on-line gaming or participating in questionable mIrc channels.