Computer Networks

Today, I'm going to talk about computer networks. A computer network is a communication system that connects two or more computers so that they can exchange information,resources and files. Different user's needs set up different arrangements of networks.


There are some common network terms that describe computer networks, which are :


(1) Node

A node is any devices that can be connected to a computer network, such as cell phones, PDA, computers and other network appliances. It is also defined as network junction or connection point.


(2) Client

A client is a program that runs on a personal computer or workstation connected to a computer network and requests information from a file server. Typically, a client is a user's microcomputer.


(3) Server

A server is a program that shares resources with other computers. Dedicated servers specialize in performing specific tasks, such as web server, printer server, database server, application server, communiction server and file server.


(4) Hub

A hub is a connection device for networks.  It allows multiple segments or computers to connect and share packets of information.




(5) Network Interface Cards (NIC)

NIC is an expansion cards located at the system unit that connect the computer to a network. It also referred to as a LAN adapter.


(6) Network Operating System (NOS)

NOS controls and coordiantes all computers' activities and other devices on a network. These activities include electronic communication and the sharing of information and resources.


(7) Host Computer

A host computer is a main or controlling computer connected to other computers or terminals. It provides data or computing services via a network.


(8)Network Manager

A network manager also called as network administrator. A network manager is a person who manages a local area communications network (LAN) within an organization. He or she is responsible for efficient network operations and implementation of new networks.


That's all for this post today. If you want to know more about computer servers, you can search it through web. Thanks!!!^^

System Unit

The system unit, also known as the system chassis,is a container that houses most of the electronic components that make up a computer system. In this new post, I will talk about system unit that can be found in each computer.

(1)Sockets [Internet]

An Internet socket, commonly called as a socket or network socket, is a communication end-point unique to a machine communicating on an Internet Protocol-based network, such as the Internet. It also used as a name for an application programming interface (ATP) for the TCP/IP protocal stack, usually provided by operating system. It connects to the HTTP daemon running on the local machine and returns the contents of the root index URL.


(2)Chips

A computer chip is a small electronic circuit, also known as an intergrated circuit. This is the basic components of computer. It is small and and made of  semiconductors that is usually composed of silicon, on which several tiny components including transistors are embedded and used to transmit electronic data signals.


(3)Slots

Slot is an opening in a computer where can insert a printed circuit board. It also called as expansion slot because it allows to expand the capabilities of a computer. It comprises the operation issue and data paths machinery surrounding a collection of one or more functional units which share these resources.


(4)Bus Lines

A bus is a subsystem that transfers data between computer components inside a compuer or between computers. It provides a data path between the CPU and attached devices such as keyboard,speakers,mouse and etc.


(5)Graphics Card

Graphics card converts information from the CPU into the display we see on our monitor's screen. It also performs special visual functions, such as reflections in computer games. If the graphics card is inadequate, the display will lack continuity, showing stutters.


(6)Sound Card

Sound card is a peripheral device in the form of a card used for producing sound and music. Although some PCs come with a built-in speakers, it was originally tied to the CPU and did not do a good job of reproducing complex sounds, this is because it takes most of the processor's power to produce only marginal sound. For sound card, it does it effortlessly and creates a much better reproduction. Most motherboards today come with some kind of external sound chip built-in, just in case we want decent sound without attaching a separate sound card.


(7)Modem Card

A modem card is necessary for us to connect to the Internet using a network. It can be wireless or installed inside of a user's PC. A wireless modem can fit into a computer's motherboard or be an external USB card.


(8)Network Interface Card

A network interface card (NIC) is an adapter which installed in a computer to provide a the connection point to a network. It provides an attachment point for a specific type of cable,such as coaxial cable, twisted-pair cable, or fiber-optic cable. NIC for wireless LAN typically have an antenna for communication with a base station. Antenna is a a metallic apparatus for sending or receiving electromagnetic waves.


(9)Plug and Play

Plug and Play(PnP) is a capability that allows users to plug a device into a computer and have the computer recognize that the device is there. It was originally a set of specific hardware and software standards developed by Microsoft, Intel, Linux and others. PnP can associated with the ability to plug any device into a computer and have it work or play immediately. However, so devices are not plug and play, they have to be installed before it works.


(10)Serial Port

A serial port is a socket on a computer used to connect a modem, data acquisition terminal or other device via a serial interface (one data bit following the other). It provides very slow speeds and has been superseded by USB and other faster interfaces for peripheral connections to desktop computers. Although still widely used in data acquisition, the serial port is no longer found on new computers.


(11)Parallel Port

Parallel port is a hardware interface that transfers one or more bytes simultaneously. It is a socket at the back of a computer for connecting external equipment or peripherals, especially printers. Although some business printers may still offer parallel ports, consumer-based printers and new computers have only USB. However, parallel port devices can be hooked up to new computers with a USB-to-parallel adapter cable.


(12)Universal Serial Bus Port

A universal serial bus port (USB) has virtually replaced serial and parallel port. It is a type of serial bus that allows peripheral devices such as modems, printers, etc to be easily connected to a computer without an adapter card nor rebooting the computer. The USB standard, developed by several major computer and telecommunications companies, supports data-transfer speeds up to 12 megabits per second, multiple data streams, and up to 127 peripherals.


(13)FireWire Port

FireWire port has a comparable speed to USB 2.0 port. It provides connections to specialized FireWire devices such as storage devices and camcorders. FireWire supports 63 devices, real-time data transfer, hot swapping and simultaneous multiple speeds. It is widely used to download video from digital camcorders to the computer and is also used in other A/V applications.


That's all for this post. Hope you can get to know what system unit is. For futher information, you can search it through webside.^^

The Internet, The Web and E-commerce

Last week, I wrote a post about careers in IT, this time I would like to post about something related to E-commerce.


(I) Business-to-Consumer

Business-to-Consumer,also called as B2C is a transaction that occurs between a company and a consumer by serving products and/or services.


(II)Consumer-to-Consumer

Consumer-to-Consumer (C2C) is a transaction that occurs between and among consumers. These transaction can also include third party involvement, usually in the form of those who facilitate the marketplace,such as eBay.


 (III) E-commerce

E-commerce commonly known as Electronic commerce or Electronic marketing consists of the buying and selling of products or services over electronic systems such as the Internet and other computer networks. E-commerce can operate all day every day, so its make transaction easily to be done.


(IV) Internet Security Suite

When a computer connects to a network and begins communicating with others, it is taking a risk. Internet security involves the protection of a computer's internet account and files from intrusion of an unknown user. Basic security measures involve protection by well selected passwords, change of file permissions and back up of computer's data.Norton Antivirus, AVG, Kaspersky...these famous products can actually protect our computer from being hacked by others, getting virus or spyware.


(V)Javascript

JavaScript is an object-oriented scripting language used to enable programmatic access to objects within both the client application and other applications. It is implemented as an integrated component of the web browser, allowing the development of enhanced user interfaces and dynamic websites.


(VI) Plug-In

In computing, a plug-in consists of a computer program that interacts with a host application to provide a certain, usually very specific, function "on demand". Add-on is often considered the general term comprising plug-ins, extensions, and themes as subcategories.


(VII) Spam

Spam is the abuse of electronic messaging systems which also including most broadcast media, digital delivery systems to send unsolicited bulk messages indiscriminately. The most widely recognized form of spam is e-mail spam. Sometimes, spam is very annoying especially you receive a lot of spam in your e-mail inbox.


That's all for today's post. If you need further information about this, you can seacrh on the Internet! Maybe you should try e-commerce and experience it by yourself one day!^^

Careers in IT

In this 21st century,Information Technology(IT) plays an important role in our daily life .There are a few careers which provided in IT :

(I)Webmaster

A webmaster is a job which in charge of maintaining Web sites for companies and individuals on the World Wide Web. A webmaster not just write computer codes or update links to other Web,but also be ultimately responsible for ensuring that a Web site is easy to navigate and that it addresses the needs of the client and its customers.Sometimes a webmaster assumes the role of web designer,however,their main job is to monitor, improve, and update the performance of existing Web sites. The webmaster must also know about the client's business and the industry to which it belongs. That's why webmaster requires a wide range of skills and abilities.

(II)Technical Writer

A technical writer,also called as a technician communicator is a professional writer who creates,design,writes,maintains and updates technical documentation.Professionals like engineers, scientists, and others may also produce technical writing, usually handing their work to a professional technical writer for proofreading, editing, and formatting.Besides, a technical writer produces technical documentation for technical, business, and consumer audiences.

(III)Software Engineer

A software engineer is a person who applies the principles of software engineering to the design, development, testing, and evaluation of the software and systems that make computers or anything containing software, such as chips, work. A software engineer not just doing codes, but also interacting with both business functions and programmers,he or she should has excellent communication skills and should enjoy working as part of a team.

(IV)Network Administrator

A network administrator is responsible for the maintenance of computer software and hardware that comprises a computer network to ensure that they function smoothly. Network technician designs and sets up the infrastructure for a computer network, a network administrator usually configures and manages an existing network. He or she may be responsible for customizing the network to an individual company's needs by connecting the necessary hardware and software to the network. Once the network is configured, the administrator adds computer programs, such as e-mail, that the company's employees use on a daily basis.


(V)Database Administrator

A computer database administrator designs, writes, and take care of computer database systems so that the right person can get the right information at the right time. He or she might set up and organize a database or reorganize an existing database. Besides,a database administrator also watches over the system to ensure that users do not tamper with the information or the structure of the database. He or she may also design programs to protect the database from computer hackers or to weed out problems in the database.


(VI)System Analyst

A system analyst analyzes business or scientific tasks and plan and develop the hardware systems and software that allow a computer to complete these tasks. Sometimes this career also called as systems analysts, may also work on improving computer systems already in use. Most of all, a systems analyst is responsible for researching, planning, coordinating and recommending software and system choices to meet an organization's business requirements.


(VII)Programmer

A programmer is someone who writes computer software .He or she writes the step-by-step instructions that direct computers to process information. These instructions, or programs, tell the computer what to do in a series of logical steps. Programmer works on a wide range of projects and does depends on the employer. Normally, programmer works in manufacturing, industry, engineering, government offices, hospitals, and educational institutions.


These are the definations of each careers in IT. If you need more information, u can search on the Internet too! ^^