IT Unit2 Blog

Connectors VGA cable: A VGA cable is used to connect your computer system to a display unit such as and monitor. It connects to the display unit via a HD15 connector. DVI(digital visual interface) cable: A DVI cable is also used to connect display units such as an monitor or a tv to the computer system. Some DVI cable can be used to carry DVI signals to a analog display. parallel port/printer cable: A printer cable is used to connect devices such as a printer to a computer system so that they are able to communicate with each other. USB(Universal serial bus) port: This is used to connect any device to a computer system that have a USB cable attached to them. For example you can use the usb port to connect peripheral such as keyboards and mice. you can also you a USB port and a USB A to Micro B to tether devices like your smartphone to you computer. Firewire: Firewire which was was developed by apple used to be a option other than USB that you could use to connect devices such as...

Example of secondary storage: Hard disk drive(HDD): This is a type of secondary storage that is mechanical. some example of the mechanical parts in a hard disk drive is the platter which is a rotating disk that contains the data and a arm which read the data off the platter. But due to his design the HDD over time can be come much slower than alternatives such a Solid State Drive(SDD). This is because over time part of file can get spread across the disk(fragmentation), This will make it so that over time it will take longer to get all the data need off the disk to run a process. You can improve this by running a disk fragmentation software that moves data on the disk that is related to each closer together for quicker access. But advantage over an SSD that a HDD has is that it's cheaper per Gb. So if you require large amount of storage you would probably be better off purchasing a HDD. Solid state drive(SSD): This type of secondary storage uses flash memory. As a result S...

Ruggedised laptop Ruggedised laptop:   A ruggedised a laptop that designed so that it can be used and will be at less of a risk of breaking in harsh environments where it wouldn't be suitable for a regular laptop to be taken to. a example of where a ruggedised laptop would be used is in the army where it would have to deal rough conditions. Some features of a ruggedised laptop would include waterproofing, a strong casing to protect the componets within the laptop against impact with a large amount of force and etc.

ROM(Read-only-memory) ROM(Read-only-memory): Read-only-memory is type of memory that has already been written during the computer system manufacturing and can only be read and not re-written, which is unlike RAM that can be read and re-written.Also another thing that's different between ROM and RAM is that unlike RAM ROM is non-volatile, what this mean that even after the power has been shut off to the computer system the data that is in the ROM does not go away. Most ROM will be in the form of a flash memory chip which is built into the mother board. What does ROM store on the computer: One program that will be stored in the ROM is the  Bios which stand for Basic input/output system. The role of the bios is to run a boot sequence when the computer is turned on to get it started so that the computer system can be used. Another role of the bios is to manage data flow between the computers operating system and attached devices such as input device, output devices and s...

RAM(Random access memory) RAM: RAM which stand for random access memory works by taking data needed by the CPU from the secondary memory(Like a hard disk or SSD) and then the CPU takes the data that it needs from the RAM so that applications can be run. If there is not enough RAM in the computer the RAM will have to access the hard drive more often, this as a result will cause the computer to slow down. To stop this from happening the simple solution is to simply add more RAM to the computer system.  But unlike some other types memory RAM is volatile which means that when the power to the computer system is shut off all data on RAM will be lost. DRAM: DRAM is where data is each bit of data is stored within a capacitor within a integrated circuit. The capacitors can either be discharged or charged to represent the two values of bits(0 or 1) SIMM(single in-line memory module): This is a type of memory module containing RAM that was used during the 80's and 90's...

CPU(central processing unit) The fetch-decode-execute cycle: This is the main cycle that happens within the CPU. The first process is to fetch the data that is need by the CPU from the main memory (RAM). Once the data has been gained from the main memory the next step is for the CPU to decode the instruction. Once the data has been decode the instruction will then be executed. The amount of fetch-decode-execute cycles that the CPU completes per second its measured in hertz, for example if a CPU has a clock speed of 3.6ghz that would be around 3.6 billion fetch execute and decode cycles per second. The control unit: The control unit is a part of CPU  that directs all the operations within the CPU. What i mean by this is that control unit will tell things like the computer memory,the ALU and output and input devices how to resound to the instructions executed by the CPU.  The arithmetic logic unit(ALU): The role of the arithmetic logic unit is to complete arithmetic...

Communication devices Router:  A router is a communication device that sends packets of data between routers on different networks so that the data packets can be delivered to the computer that has requested the data.  Advantages: There are many advantages of having router, for example a router allows users to access the internet. another advantage of having a router us that you can connect multiple devices to it which allow those devices to have a singular internet connection. Also another benefit of having a router is that i allows devices to communicate without being direct connected.  Disadvantages: If the router is sending multiple data packets to multiple devices at the same time it can cause the network speed to slow down. if you don't have any knowledge before hand it can be difficult for a person to set up a router. NIC(Network Interface Card): A network interface card is a communication device that is put into a computer system so that it ...

Input and output devices Keyboard(Input device) The role of a keyboard in a computer is to be a input device. The keyboard is used by the user to access to type instructions into the computer to be used to complete task. For example you would use a keyboard to type into documents to complete a tasks for work. The keyboard can also be used to enter shortcuts into the computer for example Ctrl+V to paste. They are different variants of keyboards such as mechanical and digital keyboard. Monitor(Output device) A monitor is an output device in the computer that displays the results of computer processes to the user. The monitor or another kind of display is needed in computer system so the user to navigate through computer and receive information from the computer, without a display of any kind computer are pretty much useless for most tasks. Some example of a use of a monitor is to show the out put of an input, for example if you were to type on you keyboard to...