Computer Fundamentals

What is a Computer

A computer is an electronic device used to process data.

A computer is a multipurpose electronic device that can receive, process and store data. Computers have different components that work together to produce the desired output.

The minimum requirements for a functional computer system include;

• a keyboard,
• CPU and memory
• and a monitor.

The data is usually entered via the keyboard and the information is usually presented through a screen; however, information can also be presented through speakers or any other output devices.

• A computer converts data into information that is useful to people.
• A complete computer system includes four distinct parts:
  • Hardware
  • Software
  • Data. The data consists of numbers, text, sound, images, animations, and video.
  • User

Memory

ROM

Read-only memory (ROM) is essential in a personal computer, or PC, as it contains the data instructions needed to start and boot it up. ROM also holds the software instructions needed by the PC to perform basic data management tasks, to access and send instructions to internal computer devices, such as hard disk drives, optical drives and graphic cards, and for some of the basic functions of a computer application.

RAM

Random Access Memory (RAM), is used by computers to store and access information using a random order. This resource provides a temporary way for computers to process electronic data, while making computers more responsive and helping operate memory-intensive programs. This memory is used when you work on different applications on your computer

Software vs Hardware

• Consists of set of instructions, executed in a sequential manner to interact with the computer, to accomplish a task. e.g., game, creating presentations. Software program is written in a programing language.

Hardware or computer hardware is the collection of physical parts or components of a computer. This may include things like, monitor, mouse, and screen. Also, components inside the computer such as Hard-drive, motherboard etc.

• Computer’s hardware consists of Electronic devices; The parts you can see and

touch. The term “device” refers to any piece of hardware used by the computer, such as

a keyboard, monitor, modem, mouse, etc.

Input Device – Keyboard

A typical keyboard looks like the one below.

It is divided into several keys.

Important key combinations

Following keys are most important for day-today operation of a computer. If you are new try these keys,

Keys	Operations
Esc	Escape/Esc key, Interrupts/cancels the current process or running program, or to close a pop-up window.
CAPS	To type continuously in Upper case
SHIFT	To make a letter in upper case
TAB	To provide a tab space
CTRL	Pressed in conjunction with another key to perform a special operation. Rarely performs any function when pressed by itself. For example, Ctrl + C is used for copy.
ALT	It is usually pressed in conjunction with another key to perform a special operation. For example, Alt + Tab to navigate to another open application.
Num Lock	Used to input numbers. Located on the right of the keyboard. User need to press the Num lock key to use the numbers. The newer keyboards don’t have a separate Numlock section.
Space/bar	To give space between text or numbers.
Enter	Used for a carriage return. When used in a word document, it gives a new line. It is also used as an OK key, which means that the current operation is completed.
Function Keys	Labeled F1 through F12, are keys that have a special function defined by the operating system, or by a currently running program. They may be combined with the ALT or CTRL keys.

Database and Database Management System

Database and Database Management System helps in storage and retrieval of data.

• A database is a repository for collections of related data or facts.
• A database management system (DBMS) is a software tool that lets users add, view, and work with the data in a database.
• Many productive applications are built around database concepts.

Databases use three main structures for organizing data:

• Fields, which store various pieces of data related to a single entity.
• Records, or collections of fields relating to an entity.
• Tables, which are collections of related records.

The two primary types of databases are flat-file databases (with only one table) and relational databases (with multiple, related tables).

Windows File explorer or Windows explorer

Also referred to as Windows Explorer or Explorer, File Explorer is a file browser found in every version of Microsoft Windows since Windows 95. It is used to navigate and manage the drives, folders, and files on your computer.

The image below shows File Explorer in Windows 10.

How to open Windows Explorer

There are several ways to open a new Explorer window, which vary slightly depending on which version of Windows you are running.

In all versions of Windows

Press Windows key+E (hold down the Windows key and press E).

Click Start and select Run (or press Windows key + R), then type explorer or explorer.exe and press Enter.

In Windows 10

Press the Windows key+X to open the Power User Tasks Menu, then select File Explorer (or press E). Click Start, select Programs, select Accessories, then Windows Explorer or Explorer.

Every folder and file have a name, date modified, type and size.

It has a path (also called address bar) too (highlighted in red) which displays the location or address of the folder/file. Path helps you in locating your files.

You can also see the number of files in a folder.

Default Drives and Folders in Windows/file explorer

Windows provides you with some default drives and folder.

C:/ drive or D drive is your main drive on your laptop and everything resides in these drives.

They are usually depicted as shown below:

This display may slightly differ depending on your organization. Your organization may have many other drives too such as dropbox, one drive or any other shared or network drives.

Default folders

Windows/file explorer have the following default folders.

• Quick access. This folder keeps all the frequently used files and folders.
• Desktop. This is your desktop folder. All files and folders present in your desktop (first screen when you switch on your computer) is present here.
• Documents. This is the default location of all the documents created.
• Downloads. This is the default location of any download you perform from the internet.
• Music. This is the default location to store all the music files.
• Pictures. This is the default location to store all the pictures.
• Videos. This is the default location to store all the videos.

Tip: These are just the default folders but you can keep your files in any folder according to your preference.

How to create a directory or folder 

Follow the below steps to create a folder.

1. Open Windows explorer
2. Open the drive or folder where you’d like to create the new folder; for example, the C: drive.  If you do not want to create a folder in the root directory, browse to the location of your choosing.
3. In Windows 10 on the Home tab, click the New folder icon.
4. You can also right-click with your mouse on a blank portion of the folder, select New and then Folder.

How to delete a folder

To delete a folder, right-click on the folder and select delete from the menu. You can also delete by selecting a folder and hitting delete key on your keyboard.

Remember:

• Deleting a folder will delete all files and folders underneath it. If a file is open on your system, it cannot be deleted.
• Simply deleting a file or folder will move it to recycle bin folder from which it can be retrieved.
• To permanently delete a file press Shift + delete on your keyboard.