Introduction to Computer

The first topic of this subject is the introduction of course.

Nowadays, we can see that workers with computer skills tend to make more money and have more satisfying careers than workers without such skills.

Basically, what is the computer? A computer is a machine that performs the four basic operations of the information-processing cycle which are the input, processing, output and storage. While a computer system is a collection of related components that are designed to work together thus a system includes hardware and software.

Hardware are the physical components of the computer including the system unit itself, as well as keyboards, monitors, speakers, mouse, storage drive bays, microphones, Network Internet Cards and etc.

In order for a computer's system to function, it needs a program. Program is a list of instructions that tells the computer how to perform the basic four operations to accomplish a task.

Software is a program that give the computer its instructions. There are two major categories of software which are the system software and application software.

System software includes all the programs that help the computer to function properly. Most important type is the Operating System (OS) i.e. Mac OS. Other part are the system utilities i.e. Help, Disk Utility, and etc.

Application software includes all the programs we can use to perform a task i.e. word-processing (Page), spreadsheet (Numbers), presentations (Keynote), emails, and most of all, Internet surfing (Safari).

Getting data in to the computer!

Data is the unorganized raw materials made up of words, numbers, images or sounds.

The first operation: Input

The input devices enable the user to enter data into the computer. This is how the computer accepts data. Examples of input devices are keyboard, mouse, microphone, digital cameras, and video cameras.

The second operation: Processing

This is where the computer transforms data into information.

Information is the data that have been simplified and organized in a way that people can use.

During processing, the computer's processing circuitry, Central Processing Unit (CPU) or microprocessor performs operations on the input data. The processor is located within the computer system's case called the system unit. Because the computer needs to juggle multiple input or output requests at the same time, it uses memory chips to store program instructions and data. Memory is essential to the smooth operation of the CPU. Most important type of memory is the Random Access Memory (RAM) which temporarily stores the program and data which the CPU interacts.

Third operation: Output

The computer provides the results of the processing operation in a way that human can understand. Output devices such as the monitor, printer, and speakers show the results of processing operations.

Fourth operation: Storage

The computer saves the data or output so that it can be used again later. Storage devices hold all the programs and data that the computer uses. Examples are Hard Drives, External Hard Drives, USB drives, Thumb Drives, CDs, DVDs and those people used back in the late 80s and early 90s like Zip Drives, Jaz Drives, Tape Drives and the one that I used when I was in lower secondary school, Floppy Drives.

We can say that communication i.e. moving data between computers is the fifth basic operation. hence, we need communication devices that enable computers to connect to a computer network.

Network is a group of 2 or more computer systems connected together, usually for the purpose of sharing input or output devices and other resources.

Most computers are equipped with modems. Modem is a communication device that enable computer to access other computers and the internet via telephone lines, cables and even wireless connections (WiFi).

Example of Information-Processing Cycle in action!

1. Input - you enter text in a word processing program i.e. Page. After done with typing in the contents, you want to run the program's spell checker program.
2. Processing - The computer checks and compares all words entered with a list of correctly spelled words.
3. Output - The computer provides a list of apparent misspellings. Then, you can correct the spelling in throughout the document.
4. Storage - You can save the revised document to your USB drive.

TYPES OF COMPUTERS

There are two types of computers which are the ones for individuals and those for organizations.

Computers for the individuals are:

Personal Computer (PC) also known as microcomputer. It is designed to meet the computing needs of an individual.

Desktop Computer are very suitable for office environment. It is a PC that runs programs to help individuals accomplish their work more productively or to gain internet access. Example Apple, Inc. iMac.

Notebook computer usually small enough to fit in a briefcase and is highly portable because many people need computer travel with them. It is as powerful as desktop and includes speakers, CD or DVD-ROM drive and a modem. Example Apple, Inc. iBook.

Laptop computer are the notebooks that usually bigger in sizes compare to the small notebook. Example Apple, Inc. MacBook and MacBook Pro.

Subnotebook are the notebooks that omit some component i.e. CD or DVD-ROM drive so as to cut down on weight and size. Example Apple, Inc. MacBook Air 11" and 13". Depends on how you see it, whether it's a disadvantage or not as you need to carry around external CD or DVD-ROM drive to open these disks.

Tablet PC is the type of notebook that has LCD (touch) screen that user can write on using special-purpose pen/stylus. Typically have keyboard for input. Example Apple, Inc. iPad and HP's Compaq.

Personal Digital Assistant (PDA) packs much of a notebook's power into much lighter package at lower price. It includes built-in software for scheduling and receiving emails. Example Apple, Inc. iPod Touch, also BlackBerry.

All-In-One Computer is a monitor with everything else built-in it. The only peripheral devices are the keyboard and mouse or magic trackpad. Example Apple, Inc. iMac.

Professional Workstations are powerful tools for architects, engineers, interior designers, graphic designers, financial analysts, who need exceptionally powerful processing and output capabilities. Example Apple, Inc. Mac Pro.

Network Computers (NCs) and Internet Appliances provide much of the PC's functionalities but at a lower price. Designed to connect to a network i.e. internet. Example MSN TV - popular during mid to late 90s.

Computers for Organizations are:

Servers are the computers that make programs and data available to people who are connected to a computer network. It is not designed for individual use and are typically centralized or operated from one location. Users connect to the network by clients (desktops, laptops, workstations) to connect to the server and obtain needed information. This use of remote or off-site clients and centralized server is called client/server computing. Size of servers are from microcomputers to mainframes. Example Dell, Sun Microsystems, IBM.

Minicomputers (mid-range servers) are mid-size computers that handle the computing needs of a smaller corporations that enable dozens or hundreds of users to connect to them simultaneously via PCs.

Mainframes are designed to handle processing jobs in large corporations or agencies. Example IBM, Honeywell.

Supercomputers are ultra-fast computers that process large amounts of scientific data and then display underlying patterns that have been discovered in the data. Used in quantum physics for an example. the latest on we have is in China, the TianHe.

I think that wraps the first lecture for this subject.

I'll post the lab practice on next entry.