Health and Safety

Health and safety is paramount when installing and changing computer components.

the main danger is static electricty, there are a number of ways to protect yourself, one way is the

ANTI-STATIC MAT

This is a mat that has 4 metal point on it for attaching a;
A) Wristband that you put on
B) A crocodile clip that you attach to the computer case
C) A plug that connects to the mains

A ANTI-STATIC PLUG

This plug connects directly to the power supply of the computer, thus preventing static electricity

The final method SHOULD ONLY BE USED AS A LAST RESORT

Place your thumb on the power supply and on the computer case, this equalizes the charge between the power supply and the computer case

Input/Output Panel

The input/output panel is located on the back of the computer and connects to many different pheriphals. The Panel tends to contain a VGA port, 2-4 USB ports, Sound ports for audio in/out, parralel ports, an ethernet port and a mouse and keyboard PS2 port.

A VGA (Visual Graphics Adapter) port is where the monitor plugs into. It is a 14 pin port with 2 screw connectors to hold it in place. A Parallel port is used to attach a printer to a computer. It is connected via a 25 pin connector. The PS2 ports are for use by a wired keyboard and mouse, wireless versions use a USB port. The Ethernet port uses an RJ42 connector.

Storage Devices

Storage Media

Storage Media is a place to save data to. The storage media can be in a variety of objects, such as  Internal Hard Drives, External Hard Drives, USB pens, Portable Hard Drives and CD and DVD disks.

HARD DRIVES

Hard drives are drives that store data in a computer, unlike external and portable drives, Hard drives are located internally, i.e inside the computer. An Hard Drive can have different capacities, such as 250 or 500 GB (Giga-Byte), and can go up to 1.5 TB (Tera-Byte) in size. The are normally connected by a 4-pin connector to a ribbon (See Power supply for details). To Remove a Hard drive, first unscrew the connector screws on the side that hold the hard drive in place, then remove the 4-pin connectior gently, you should also remove the 20-pin power connector. Then gently pull the hard drive out of the computer casing. To reconnect the hard drive, carefully slide the hard drive into the computer casing, then re-attach the screws to make sure that it doesn't slide out. After this carefully re-attach by gently inserting the 20-pin power cable into the slot on the hard drive and the 4-pin cable into it's slot.

External hard Drives

External hard drives are just that, the same as an internal hard drive with the same capacity but are located outside. To attach an external hard drive connect the USB (Universal Serial Bus) 2.0 Plug into the external hard drives slot and connect the power cord to the external hard drive.

Portable Hard Drives
Portable hard drives are like external hard drives, but do not require a power supply, instead they run off the computers own power. All you need to use a portable hard drive is a USB2.0 cable, and attack it into a USB2.0 slot on the computer. They have a maximum size of 500GB, any higher and they would be a external hard drive.

USB Pens

USB Pens are a easy way to carry media. To use just insert the pen into the USB 2.0 Connector on the computer. USB pens vary in size, up to 32GB

CD/DVD Disks

CD (Compact Disks) are mainly a form of storage media for music file formats while DVD's (Digital Versitile Disks) can be used to store video, music or just plain data formats. These disks that can be written using a CD/DVD burning program and are affixed with RW at the end, for example CD/RW means that it is a Compact Disk and can be Written too, overwriting any other data on the disk.

Features and functions of different operating systems

Since there are a number of different operating systems around, I will compare the Linux kernel OS with the latest version of Windows along with MAC's


Linux is a freeware operating system that has been provided in a number of different systems, that are all based around the basic "kernel" that is at the centre of all linux systems. Each different system has a different interface depending on what the developer decides it wants it to be closer to, for example, the "Puppy" version of linux has a interface that is similar to windows, while the "Ubuntu" version has a interface that is closer to the Mac operating system. When Linux when it first started it was closer to a MAC system, so in it's early days it was essentially a freeware version of MAC.

Windows, in comparision is firmware, and as such offers more functionality such as a on-screen keyboard. It's interface is a basic desktop, and each application runs in a seperate "window". There have been many different versions of windows, from windows 95, up to windows millenium , which was a special edition that was released from october 1998, while another version windows 2000, was released from febuary 2000, these 2 were the last kind of the old windows interface, as when windows xp was released, the interface was totally re-designed to include a new windows start button, but retained the option to revert the start menu and the task bar back to the old windows format. The interface was again redesigned when windows vista was released, with the start button being re-designed again to a simple round button with the windows logo on.

Overall, both operating systems have their individual advantages and disadvantages, with Linux being at a disadvantage over drivers, since it is not what people would call a 'mainstream' operating system, while Windows has the advantage of being a 'mainstream' operating system, but has it's disadvantages in that it has major rivals to contend with, and as a result, they tend to rush development of operating systems, Windows Vista is an example of this, as it was well publisised, but had so many bugs, that people avoided using it, this was fixed by the release of Windows 7, which is what Vista was supposed to be.

Macintosh computers which are produced by Apple.inc are the main rival to Windows, and it's computers tend to focus on the graphical edting of images, and as such are used in all of the major corperations, however software for MAC computers tends to expensive, whereas software for Windows is average. In terms of the Price of software, Linix is the real winner since most of it's software is free, but again does not have the specilised aspect that paid for software has, for example , Linux cannot support Adobe Photoshop.

In terms of ease of use, there is no clear winner, as users of each system say that there's is the easiest to use, while other people may differ.

Operating Systems

An operating system is a system that directly controls all of the basic operations and hardware within a computer, while also providing a basic foundation on which to run applications, and as a result they are the first thing that is loaded when the computer is started up. They normally come with pre-loaded programs. Overall  there are 2 different types of operating systems, command driven and graphical driven. Command driven is when the user inputs commands into a terminal. This type of operating system is easy to use provided that you know all of the commands. The second type, the graphic driven is what we are most used to, this type of operating system uses a graphical user interface that uses windows. Some examples of graphic operating systems are;

Windows 7
Windows Vista
Mac OSX leopard
Linux
Sun Solaris

There is also the option of a command driven interface for Linux.


Mac OSX

The Mac Operating System is provided by Apple and is mainly used for graphics work. It is a main competitor to Microsoft Windows.

Along the bottom of the screenshot is the quick access toolbar that lists the most used applications while along the top is the menu that contains various options to help the user, such as file, edit, view, window and help.


Linux

Linux is a freeware operating system loosly based of the Mac OS system, and as such contains many of the features of the same system. It is however based around a central Kernel. Linux comes as both a command driven and Graphic driven interface

This is the command driven interface for the Linux OS system, as you can see. Depending on the user, the command driven interface can be very fast to use but for new users, it is quite difficult to use.

This is the graphic user interface for linux, depending on the version they differ, in this version, the user interface looks more like windows but in other versions it will look like MAC but it depends on the type of linux being used, some examples of Linux are Ubuntu, Puppy, Kubuntu.

Windows 7 and Windows Vista

These two versions of Windows are produced by Microsoft, and are the main contender to the MAC OSX system. they use a graphical user interface using the concept of windows for each application. It is one of the main operating systems.

ROM

The ROM stands for read only memory, which can only be read, not written to. Unlike RAM, ROM keeps it's memory after the computer is shut down. ROM generally contains the operating system infomation, along with user folders and system infomation. ROM cannot be removed as it is soldered onto the motherboard. ROM is programed at the factory with pre-determined infomation, and as such cannot be modified to add or remove infomation.


ROM is also found in other electrical objects, such as GPS, SatNav and Gaming Consoles.

ROM

BIOS

The BIOS (Basic Input Output System) is a small chip that makes sure that all of the other chips and cards are functioning correctly. There are a few different types of BIOS, such as the soldered ones, which are soldered directly to the motherboard, there are also catched BIOS, where there is a small catch holding the BIOS in. The BIOS is also involved in helping to boot the Operating System up. It has it's own power supply coming from the CMOS battery, which keeps track of time and other infomation

The only reason as to why you would need to replace the BIOS is if it fails, otherwise the BIOS does not need replacing. The BIOS performes a POST (Power on self test) test during the start up sequence on all of the components such as the Hard drive and any disk drives and also activating any other BIOS chips such as those that can be found on the Graphics card.

When you initially start the computer, the BIOS does the following;

1. Check the CMOS Setup for custom settings
2. Load the interrupt handlers and device drivers
3. Initialize registers and power management
4. Perform the power-on self-test (POST)
5. Display system settings
6. Determine which devices are bootable
7. Initiate the bootstrap sequence

When you need to update the BIOS, you need to go to the manufactuers website and download the upgrade along with a small utility to install it.