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Monthly Archives: November 2016

Computer Hardware

Computer hardware consists of electronic and mechanical elements of a computer. The hardware includes the system unit which has components such as the motherboard, CPU, chipset, hard disk, RAM, video card, and sound card. The hardware also includes the peripherals that are used for input, output, and storage of data.

Different Kinds of Computer Hardware

Other than the hardware formats mentioned earlier, there are other types of computer hardware as well. For example, the CPU processes and manages information and can be called the brain of a computer. Then there is the internal bus that connects the motherboard to the video and the sound cards, and the PCI bus that connects the hardware devices to the computer. There are also the northbridge and the southbridge form the core logic chipsets, which control the exchange of information between the hard disk and the computer. The northbridge connects the southbridge to the computer, and they both determine how fast the system can access memory. The external bus is controlled by either the southbridge or the PCI bus. The chipset is used for communication between the CPU and the memory.

The RAM is the random access memory that stores and processes the information that you’re working with. The RAM is faster than the hard disk, but it is volatile, which means that it stores information temporarily and loses all information when the power is switched off. The types of RAM are SRAM and DRAM. The BIOS is the Basic Input Output System and consists of the firmware. The firewire connects a digital video camera to the computer. The SATA connects the hard disk drives to the computer, while the eSATA is external SATA.

A hard disk drive consists of platters with magnetic surfaces and it stores information which is not being processed. A hard disk is non-volatile, which means it stores information permanently and the information is not lost in times of power failure. The types of hard drives are IDE and SATA. A solid-state drive is similar to a hard drive but it is not magnetic. The removable drives include a CD-ROM drive that reads CDs; a DVD-ROM drive that reads DVDs, and a BD-ROM drive that reads a Blu-Ray disk. A CD-writer writes data on a CD and is used for the backup of files. A DVD-Writer writes on DVD, while a DVD-RAM also writes on DVD but it supports more rewrites than a DVD-Writer. A BD-Writer writes on the Blu-Ray disks. Some old computers still have a floppy disk drive that reads a floppy disk, though those computer systems are now technologically almost obsolete. A USB flash drive reads flash memory. It is small, light, pocket-sized, and portable.

The graphics card provides information to the screen, and is used to render graphics in a computer. A monitor, which may be CRT or LCD, displays the images and videos in a computer by manipulating the color of the pixels on screen.

A sound card plays sound files, produces sound for the speakers, and receives sound as an input from a microphone. The speakers output audio such as music and sound effects, and the headphones are used for hearing sounds that are only meant for individual hearing.

You can also plug-in peripherals, for example, input devices such as a keyboard or a mouse which accept user inputs and convert it into digital data. A user can type using a keyboard, which has various letter and number keys, special keys such as Esc (Escape), Ctrl (Control) and Alt (Alternate), and function keys such as F1, F2 and F3. The Caps Lock key allows the user to type capital letters, while the Tab key moves forward the cursor to the next tab stop. Shortcut keys are a combination of two keys pressed at the same time, and arrow keys on the computer keyboard serve as navigation keys. The numeric keypad of the keyboard has a layout similar to that of a calculator. When the Num Lock key is on, the keys become a numeric keypad, and when the Num Lock key is off, the keys can be used for navigation.

A mouse has a wheel and two buttons that allow you to click, double-click and drag items. When a mouse is moved on a mouse pad or any flat surface, the pointer on the screen also moves. An optical mouse is a mouse with laser of LED technology. A trackball is a device containing a ball that can be rotated in a socket. Joystick and gamepad are two of the other very popular input devices.

A desktop computer system also includes a scanner, which analyzes images, and a webcam, which provides video input. A modem sends and receives data through telephone cables and facilitates Internet access. A printer produces text or pictures on paper.

A power supply gives power to a computer from an electrical wall outlet. The PC case can be vertical or horizontal, and the cables and wires are also considered part of its hardware.

In the future, there will be quantum computers and electronic paper, used in e-book readers. The future of hardware is very promising. CPUs will get faster, hard drives will have more storage space, and computers will get more powerful. Their speed and power will revolutionize the world.

Computer’s BIOS Setup

What happens when you turn on your PC? Lights come on the keyboard and monitor, the computer’s brand logo may appear on the screen, then the operating system loading message appears. This is all occurring on screen, but in the background, your computer is actually powering on and preparing its external and internal parts. Many assume the Operating System (OS) is the first program a computer loads and operates on but the actual start-up program is the BIOS.

BIOS stands for Basic Input/Output System, which is inbuilt in every PC during manufacturing and is loaded, run and executed when you press the power ON button of your PC. The BIOS is a sort of firmware interface for a computer. Different components, such as pen drives, graphics card, keyboard and mouse and disc drives attached to a computer, need to be initialized and identified to the computer. The BIOS does this in the form of a check-list (“turn USB ports on”, done) and this procedure is known as POST (power-on self-test). The operating system itself is a program, which needs to be loaded and executed. This too is performed by the BIOS, which locates the OS program on the computer’s hard disk and runs the program. One needs to enter the BIOS interface to change various system-level settings, such as changing the system clock, changing the boot up drive and managing memory. Listed below are the steps on how to access the computer’s BIOS setup.

How to Get Into Your Computer’s BIOS?

Step 1: Start your PC or restart it. When the computer starts up, usually the manufacturer’s logo or the brand name of the PC is displayed on a black screen. In some cases, the screen turns into the logo of the operating system and a “loading” or “starting” message appears on the screen. At such booting screens, a small message is displayed, which has the combination of access keys needed to enter the BIOS. Examples of such messages are:
– Press “key” to enter BIOS
– “key” = Setup
– To enter the BIOS setup, press “key” + “key”
– Press “key” to access system configuration
– Press “key” to enter the Setup menu

In some computers, the manufacturer’s logo or brand name shows up and no message for entering the browser occurs. So try pressing the Tab or the Esc key to remove it. You can either note the key down or if the screen changes too fast for you to enter the BIOS, press the Pause/Break key on your keyboard. This key will pause the booting screen, so you can understand which keys are needed to access the BIOS. To unpause such a screen, press any key.

Step 2: Once you know the access key combinations, then press that key or press the combination of keys during the booting screen to enter the BIOS interface. In some computers, just one press of the key is enough, with others, you may need to tap it repeatedly. Do not press and hold down the key with force or press it too many times. The system may hang or an error code will show up on screen and you will need to restart your PC. With certain machines, pressing the DEL key repeatedly at the boot up screen, before the OS loading screen appears, can bring up the BIOS screen. Other common BIOS keys are F1, F2, F10, F12 and ESC.

Step 3: The BIOS is not dependent in any way on the operating system. So whether you are running Windows 7 or Mac OS X, the OS has nothing to do with your BIOS and hence different operating systems does not mean different BIOS access keys. Instead, your computer’s BIOS depends on the manufacturer of the motherboard, like Acer or ASUS. So there are proprietary access keys to enter the BIOS screen, based on the brand of the computer. Some computer systems and their BIOS access shortcuts are:

Manufacturer                   Access Keys
Acer                                    F1, F2, CTRL+ALT+ESC
Compaq                             F10 (newer), F1, F2, DEL (older models)
Dell 400                            F3, F1
Dell 4400                          F12
Dell Inspiron                    F2
Dell Latitude                    Fn+F1, Fn+ESC
Gateway 2000                 F1
Hewlett-Packard (HP)   F1, F2, ESC (for laptops)
IBM                                    F1, F2 (E-pro laptop)
Micron                               F1, F2, DEL
Packard Bell                     F1, F2, DEL
Sharp                                 F2
Sony VAIO                        F2
Toshiba 335CDS              ESC
Toshiba Portégé               ESC
Toshiba Satellite              F1
Toshiba Tecra                   F1 or ESC

Warning: The above-mentioned access keys may differ from computer to computer, so always verify the information prior to usage. The correct access keys are provided as a part of the computer’s documentation. This site does not assume any responsibility for any issues that could occur by using the above information.

The BIOS is a rather sensitive part of your computer’s internal makeup, so pressing a lot of keys at the boot up screen is not a good idea, unless you know what you are doing. So do not press any or all keys in tandem or with force to enter your computer’s BIOS. Instead, refer to your computer’s manual and look for System Settings or similar headings to find the correct BIOS key. You can even search online using your computer’s model number and make.

Once you have actually accessed the BIOS and are facing the lovely light blue screen, here’s a word of caution; fiddling with BIOS settings is not for novices or the ill-informed. If you know what you are doing, then only change settings and to be safe, write down what you are changing, in case you need to go back and re-change it. Use the arrow keys and function keys to navigate and select options within the menu. Accessing the BIOS of a computer’s system can be done to change certain basic computer settings and workings, but should be carried out with caution.

Network Hardware

A computer network is not made up of one machine or even one type of machine. It is a carefully designed system of different hardware components (networking devices) working in tandem with various rules and communication protocols. From the network scenario in a household, to a medium scale network in a school or mall to a large, border-crossing network of a corporation or service, a computer network is made up of various hardware parts, some standard and some rare and more complex. So, what are the different types of network hardware? Read on for a listing of such devices and a brief explanation of each.

Types of Network Hardware

Cables & Wires
Everything may be turning wireless nowadays but at least 2-3 wired connections have to exist somewhere in a computer network. Connecting a desktop to a router or the router to the modem, such connections are always wired and the common cable type used is CAT5 RJ-45. Wiring is typically thought of as being a Layer 1 (physical layer) device as raw data or signals are transferred from one end to the other.

NIC
Network interface cards is easily one of the most important components of a computer network. It is a hardware part that allows the computer to be identified amongst others in a network and allows the computer to connect to a network. It works in the physical and data link layer of the OSI model. This card provides the circuitry required to implement a networking standard. The most common NIC form used is Ethernet. Recent computers, both desktops and laptops have their NIC built on the motherboard, earlier computers needed an internal or external NIC to be added. Laptops with built-in Wi-Fi have wired and wireless NIC capability, but most desktops have only wired connection capabilities and will require a wireless adapter to connect wirelessly.

Hubs
Connecting more than one computer to a higher layer networking device like a router can be difficult, if you do not have a hub. A hub collects various devices through a wired connection and groups them into a segment. So, the network recognizes all devices connected to the hub, as one segment. Typical hubs allow Ethernet wired connections and have at least 4-5 ports on them and can have 8, 12 or even more ports. They are very simple devices, they do not manage or filter or function in any other manner, other than to act as a collection point. They operate in the physical layer of the OSI model.

Modems
A modem acts as a sort of converter or translator. It allows digital data or information to be transmitted over traditionally analog lines of transmission such as a telephone line. The word “modem” is a mix of two transmission terms, “modulate” and “demodulate”, which are the two main operations performed. The digital signal from a computer is converted into analog form, sent over the analog medium and then decoded back into its digital form at the receiving end.

Routers
Routers can be thought of as the mailroom of a network. They receive incoming data packets, decipher their addressing information (where did they come from, where do they have to go) and send them accordingly. Routers are essentially used for traffic management. They function in Layer 3 (network layer) of the OSI model. Routers are much smarter than hubs, they can implement security protocols, assign IP addresses, both static and dynamic and can function in both the wired and wireless transmission band. There are different router types based on their area of use, such as home or small-use routers to enterprise routers, which are used for complex routing functions in large corporations.

Gateways
A gateway acts as the meeting point or go between point between 2 different networks, using different protocols. e.g. Network A uses one protocol, Network B uses another. A computer from A wants to communicate with a machine from B but due to the difference in protocols, it does not know how to communicate. It can adopt or add B’s protocol but this is a tasking process and is not really efficient. Instead, a gateway will translate the request from the computer in A’s network, into B’s language and then translate the reply from B’s language into A’s. So, the 2 machines can communicate without any change in protocol. Gateways function in all layers of the OSI model, since they perform conversion or translation functions.

Wireless Access Points
An access point acts as a middle station for a network and helps in adding more users to it. They are connected to the network but act as a transmitter and receiver for the network signals, so other devices can connect to the access point and in turn will be connected to the main network. The best example for an access point scenario is a large house, where the router is located in the basement. So, the ground floor can receive the wireless signal but the first floor cannot, due to the network’s limited range. An access point connected on the ground floor will receive the router’s wireless signal and emit it to reach the first floor, enabling users on that floor to access the original network.

With advances in technology, the features and specifications of such devices may change or the device itself may become obsolete. But for now, this collection of network hardware remains constant; and at least one or two of the above devices can be found in any computer network.

What is a Bit and Byte?

In this age and time, one has to know a lot of words and acronyms in every field that we come across. With specialized fields of knowledge emerging every day, new technical terms keep cropping up. Bits and bytes are terms which you often come across when dealing with anything in electronic or computing field. The paragraphs below will give you a gist of the same.

What is a Bit and Byte?
A bit is actually an acronym, which stands for ‘Binary Digit’. It is the smallest possible unit of information in digital computing.
Computers do not use decimal numbers to store data. In computers, all data is stored in binary numbers. They are all based on binary digital logic.
Every bit can take only two characteristic values either 0 or 1. For computers and in digital communication, a bit is the smallest amount of information stored in binary form.
In digital telecommunication too, all the voltage levels are converted into binary form of data or bits.

Origin
The origin of the term ‘binary digit’ or ‘bit’ is attributed to John Tukey, a scientist who worked at the Bell Laboratories, who first used it in 1947.
Since then, the term has been in use in the world of computers.
A byte is a string of 8 bits put together. A byte is therefore a bigger unit of information than a bit.
The term ‘byte’ was first used and coined by Dr. Werner Buccholz, a computer scientist working at IBM, in 1956.
The Binary Number System
Just as, including zero, the decimal number system is based on ten numbers, the binary number system has just two numbers 0 and 1.
All the data that a computer processes is in the form of 0s and 1s. These bits are represented by dual voltage levels in digital communication.
If you have watched the science fiction movie ‘Matrix’, you’ll remember how the whole matrix is seen as an imaginary digital world, made up of 0s and 1s by ‘Neo’, the protagonist of the movie.
Setting the fictional part apart, that is actually how computers see data, which is a stream of 0s and 1s or stream of ‘bits’.
The computer converts all data into bits and bytes through alphanumeric and decimal to binary conversion.
So, for the computer, alphabets and letters are all represented in bits. That is, bit is a letter of the computer language, while a byte is a word (made up of 8 letters).
Interestingly, a four bit binary word is called a ‘nibble’, because it is half a byte.
You must have come across the terms bits and bytes when checking out capacity of data storage devices or bandwidth of your Internet connection.
The capacity of the computer hard disk is given in giga bytes (abbreviated to GB) usually.
A GB or gigabyte is a billion bytes or eight billion bits. Data transfer rates are always mentioned in bits. The internet is an ocean of bits and bytes.
Computer chips are of two kinds: 32 bit and 64 bit. This denotes the amount of data that can be processed by the chips or read at a time. The Internet bandwidth is measured in kilobytes (thousand bytes) per second, that is ‘kbps’ or mega bytes per second (MBPS).

The twenty first century is the age of information technology and therefore, bits and bytes are terms which will be increasingly heard around the world even in the future.