Operating systems

This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.

Skills: none

IT concepts: popular operating systems, open-source vs proprietary software, operating system functions, device drivers, TCP/IP, virtualization

Where does this topic fit?

• Internet concepts– Applications– Technology– Implications for

• Internet skills– Application development– Content creation

Popular operating systems

Windows 7

OS X

Linux

Popular operating systems

ProprietaryMicrosoft

ProprietaryApple

Open source

Open source

• Free as in free beer

• Free as in free speech

Main things the operating system does

• Execute user commands

• Manage files and their locations in storage

• Switch the CPU from one program to another

• Manage memory and storage

• Interface with hardware devices.

Graphical user interface (GUI)

Command line user interface (CLI)

Execute user commands, delete a file

Drag to the recycle bin

Execute user commands, run a program

Manage data and program files

Allocate CPU time

Windows task manager: Ctrl+Alt+Del

I could be doing a foreground task like word processing or Web surfing at the same time.

Transferring two files to another computer at the same time

Manage memory, storage and other resources

Windows resource manager: Ctrl+Alt+Del > Resource monitor

• Memory garbage collection

• Disk swapping

• Others

Slugish PC needs more memory

Interface with I/O, storage and other devices

You might add new input output and storage devices to your computer after you buy it, so the operating system must be open-ended.

New devices come with interface programs called device drivers.

Operating system

Driver for device 1

Driver for device n

Driver for device 2

Driver for device 3

...

Memory

The Internet is essentially a (very big complex) input and output device for a computer connected to it.

The interface programs for the Internet have the catchy name TCP/IP.

Operating system

Driver for device 1

Driver for device n

Driver for device 2

Driver for device 3

...

Memory

TCP/IP

Device interface programs are called device drivers

Interface with the Internet is a suite of programs called TCP/IP

TCP/IP is like a device driver for the Internet

Prog Doc

Operating system 2

... Prog Doc

Operating system 3

...Prog Doc

Operating system 1

…

Virtualization

Windows and Mac OS-X

But, virtualization is primarily used on servers.

A few questions

We covered five of the most important things an operating system does. Without looking back, can you recall what they were?

Is a device driver hardware, software, or both?

When you purchase a new device like a Web camera, who supplies the device driver?

Do popular operating systems like Windows include TCP/IP or must you download and install it before you can connect your computer to the Internet?

Device drivers

If a vending machine were connected to the Internet, would it need a computer inside? Would it have to run TCP/IP software?

There are no applications running, yet 51% of memory is in use. Why is that?

There are no applications running, yet 13% of CPU capacity is tied up. Why is that?

Operating systems

This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 License.

Skills: none

IT concepts: popular operating systems, open-source vs proprietary software, operating system functions, device drivers, TCP/IP, virtualization