What are the Parts of the Computer System Unit?

This article introduces you to the parts of the computer system unit. A desktop computer is designed to be placed on top of a desk or table while in use. It comprises the system unit and peripherals such as keyboard, mouse, and monitor.

The system unit is the box-like case that contains or holds the computer’s electronic components together. Another name for the system unit is the chassis or main unit.

The term system unit is only applicable to desktop computers. It cannot be used with the devices that combine the monitor and system unit such as laptops and Mac computers. There are those who erroneously refer to the system unit as the processor.

The processor is the main chip or integrated circuit found on the motherboard. It fetches and decodes program instructions.

The Computer System Unit showing the front side and the back side
The System Unit

Functions of the System Unit

The main function of the computer system unit is to hold all the other components together. The chassis protects the sensitive electronic parts from the outside elements. Most system units are upgradeable. You can perform various types of upgrades such as adding a card, or a second hard disk drive.

The computer system unit front part contains various ports required by a user frequently. These are the USB ports, audio ports, optical disk drives, and the power button.

At the back of the system unit, you will find a number of other ports. These are for peripherals such as the monitor, keyboard, mouse, Internet connection, and a wide range of other peripheral devices.

Major Components of the System Unit

These are some of the major components of the system unit. To see any of these, you have to open the chassis or the system unit. Before opening the system unit, it is important to follow ESD precautions.

The Computer Motherboard

As you may know, the motherboard is one of the major parts of the computer system unit. The motherboard, system board or the mainboard is the main circuit board of a microcomputer.

The motherboard contains the connectors for attaching additional boards. Typically, the motherboard contains the CPU, BIOS, memory, mass storage interfaces, serial and parallel ports, and expansion slots. It also contains all the controllers required to control standard peripheral devices, such as the display screen, keyboard, and disk drive.

The motherboard is one of the major parts of the Computer System Unit
Computer Motherboard

There are different types of motherboard form factors. The term motherboard form factor defines the general shape of the motherboard, the type of case, and the power supply it can use.

It also describes the physical organization of the motherboard components. Various input-output ports protrude at the back and front of the computer. They originate from the motherboard. They communicate with the various input-output devices used by a computer.

There are two types of computer ports;
  • Internal ports – These connect the motherboard to internal devices like the hard disk drive, optical disk drive, internal modem, among others.
  • External ports – These ports connect the motherboard to external devices like modems, mice, printers, and flash drives among others.

Internal Hard Disk Drive, Found Inside the Computer System Unit

This is a high capacity magnetic data storage media with a volume (disk) this is usually non-removable. Mostly it holds the operating system, the application programs, and user data. Nowadays we have portable hard disk drives that are used to store and transport data.

There are different types of computer hard drives.

  • Parallel Advanced Technology Attachment (PATA)
  • Serial ATA (SATA)
  • Small Computer System Interface (SCSI)
  • Solid State Drives (SSD)
The internal computer hard disk drive commonly found inside the computer system unit
Computer Hard Disk Drive

Floppy Disk Drive

The floppy disk drive (FDD) is a disk drive that can read and write to floppy disks. Floppy Disk Drives were used in the early days of the personal computer. They are obsolete nowadays.

The floppy disk drive is one of the Computer System Unit componets
Floppy Disk Drive

Optical Disk Drive

Desktop computers come with a device called the optical disk drive. This is a disc drive designed to use laser light or electromagnetic waves within or near the visible light spectrum for reading or writing data to or from optical discs (CDs and DVDs). Modern drives can read and write on various optical discs.

An optic disk drive found inside the Computer System Unit
Optical Disk Drive

Computer Data Cables

The computer data cable carries data from the drive to the motherboard and vice versa. There are two common types of data cables, the SATA data cables and the EIDE data cables. You will find EIDE data cables in older types of computers.

IDE data cable is another example of a part of the Computer System Unit
Computer IDE Data Cable: Source
SATA Data Cable
SATA Data Cable

Power Supply Unit

The power supply unit (PSU) converts the mains alternating current to different direct currents voltages required by the computer components. It supplies power to various components within the system unit and above all, to the attached peripherals.

Modern desktop computers use switched-mode power supplies. This is a type of power supply that makes use of a switching regulator to convert electrical power efficiently.

The power supply unit
Power Supply Unit

Computer Fan

A fan is another component found inside the computer system unit. Its main work is cooling the components. It is designed to draw cooler air into the computer system case and drive out the warm air. The fan also moves cool air across the heat sink of various components such as the processor and chipsets.

A computer fan
Computer fan

Introduction to Personal Computer, Definition and a Comprehensive Guide

Topics Covered in the Session

  • Computer history
  • The first Personal Computer
  • What is a Computer?
  • The components or parts of a computer

Computer History Way Back Before Personal Computers

This introduction to Personal Computer will let you know the basics of a computer. Many discoveries and inventions have directly and indirectly contributed to the development of the Personal Computer or the PC as we know it today. Examining a few important developmental landmarks can help bring the entire picture into focus.

Labeled Computer Parts Showing Some of the Different Parts of a Personal Computer
Labelled Computer Parts

The first computers of any kind were simple calculators. They were invented with the main aim of aiding in calculations. For instance, in 1880 the American population was so large that it took more than seven years to work out their census results.

This led to the need of inventing a faster way of crunching numbers. The first types of machines that we call the first computers were invented during this period. These were the punch card based computers that filled an entire room.

Over time, those mechanical computers evolved into the electronic digital devices that we have today. Their sizes changed drastically over time from football and room filled sizes to pocket-size devices of the modern day time.

The First Personal Computer

The term PC refers to a Personal Computer, the kind of a computer designed to be used by one person at a time. The first Personal Computer was invented by IBM back in 1981.

A personal computer is a general-purpose computer, whose capabilities, size and cost price are ideal for an end-user. The components that make up a computer can be classified according to its functionality.

Before looking at specific computer components, it is worth taking a few moments to consider the key functions which are performed by every single computer.

What is a Computer?

This question has been asked a million times and if you go to the computer books or the web, you will get almost the same answer.

A computer is an electronic device or machine that responds to a specific set of commands or instructions and it can execute these instructions.

The computer performs calculations and executes instructions that are provided by a software or hardware program.

The diagram below illustrates how a computer executes a command. The input device produces the instructions that are then passed to the processor, which does the processing to determine what the command is supposed to do.

It then communicates the results of the processing through the output devices or stores them for future use.

Note that the word computer came from the Latin term ‘computare’, which means to calculate or compute.

Parts of a Computer
A diagram showing parts of a Computer

The Components or Parts of a Personal Computer

A computer is designed to accept instructions or commands through input devices. It then processes the instructions received and produces an output of usable information.

This information can also be stored using a number of storage devices available. A fully functioning computer will have the following parts.

  • Input devices
  • Processing device
  • Storage devices
  • Output devices

Computer Input Devices

Input devices are used to enter raw data into a computer. They offer an interface or a link between the user and the computer. These are just but some examples.

Computer Keyboard

Keyboard

The various keys on the keyboard let you enter information into a computer. For instance, whenever you are typing on a keyboard, you are issuing commands to the processor.

Mouse

A mouse is a hand-held device that helps you select, give commands, and move items on your screen. A mouse can come in various shapes, colours and sizes.

Scanner

A scanner is a device that reads graphics and text and feeds the data into a computer.

Joystick

A joystick helps you control the movement of people and objects in many games. Joysticks are used for arcade-type computer games because they let you move quickly and accurately in any direction.

Other input devices include Touch Screens, Digital Cameras, bar code readers, and Microphones for voice input among others.

Processing Device

The processor is the main chip in a computer. It is also known as the Central Processing Unit (CPU). Its main work is to fetch, decode and execute program instructions. It also performs arithmetic and logical operations.

The processor manipulates raw data and manages how the information flows through a computer system. It communicates with input, output and storage devices to perform any kind of task given to it. The computer processor also controls the operation of other components in the system.

A Computer Process that fetches, decodes, and executes computer instructions
A Computer Process

Computer Storage Devices

The computer storage devices are divided into two; Primary storage and Secondary storage. The main primary storage device used in a computer is the RAM or what is commonly known as memory. Primary storage stores data temporarily.

The secondary storage is used to store data permanently. It can either be internal or external. These are some examples of secondary storage devices.

Hard Disk Drive

The hard disk holds information permanently ready to produce the info when needed, after one day, one year or for any period of time. The information could be filing names and addresses in a database, pictures, music, videos, digital books, and software, among others. There is no point in processing or storing information unless it can be accessed again, and that is where storage devices come in handy.

Computer Hard Disk Drive for permanent data storage.
Computer Hard Disk Drive

USB Flash Disk Drives

This is a portable storage device that comes in a small and compact size. It connects to a computer via USB ports. Flash disk drives are an easy way to store and transfer data between computers and they range in different sizes.

Computer Output Devices

Output devices give us an output of what has been processed and as we say, information in, information out. This could be the printing of a list of names from the database or displaying the picture on a web page. They include: –

Monitor

A monitor displays text and images after being processed in soft copy.

A Computer Monitor

Printer

A printer produces a paper copy (hard copy) of the information displayed on the screen.

Computer Speakers

Computer speakers are hardware devices that transform the signal from the computer’s sound card into audio. Most computer systems will come with internal speakers which are not that powerful.  

If you want great sound, surround sound, fuller bass, or just a better quality of audio, you better buy external computer speakers. If you are a sound person, just go for a surround sound system.

Headphones

They allow you to listen to audio in private without other people snooping into what you are listening to. You will also not disrupt other people in the vicinity. They connect via the computer line out, or to the speakers.

Projectors

A projector is an output device which projects computer images onto a wall or screen. Projectors are typically used for presentations, watching movies, or as a teaching aid, as their output area is wider for an entire roomful of people to see images generated by a single computer with much ease.

Conclusion

Thanks for reading. If you need more information, I can recommend the CompTIA A+ Certification All-in-One Exam Guide, Tenth Edition. This book will offer you amazing materials for reading and revision. Once done with it, you will become a professional in the IT world.

Introduction to Personal Computer

How To Link Business and Update Beneficial Ownership Information

These simple steps will enable you to link business on the eCitizen portal. This is for both Business Names and Limited Companies.

The Companies Registry Department set up a digital Business Registration Service (BRS) in the year 2016.

The E-citizen portal hosts the service for registering and managing businesses in Kenya.

This made business name and company registrations much easier because one does not have to go to Sheria House physically.

Name search and business registration of either limited or partnership is achieved through the eCitizen portal.

All the necessary documents including the business registration certificate are issued online.

When Linking a Business on Ecitizen Portal, first step is to log in.
Ecitizen Login

Why Link a Business on eCitizen Portal?

Businesses registered before the introduction of this digital platform must be linked. This is to ensure details are captured by the Business Registration Service.

All prior registered entities such as; companies, including public limited companies, companies limited by guarantee, foreign companies as well as limited liability partnerships and sole proprietorships must be linked to the eCitizen Portal.

The link option requires clients to give details of their business entities which in turn are verified against the data held by the registrar.

This means that only the proprietor, directors/shareholders or a Certified Company Secretary (CPS) can utilize the “link business” option.

What You Require to Link a Business on Ecitizen Portal

You will require the following details to be able to complete the linking of a business process:

  1. Designation of the company officials (i.e. proprietor, director/director shareholder/shareholder/ company secretary).
  2. Copy of the Business Registration Certificate you are linking.
  3. Telephone numbers of the directors and the company.
  4. Email addresses of the directors and the company.
  5. Postal address of the company and the company officials.
  6. County, district, locality, and street where the director or proprietor resides.
  7. Identification Number(s).
  8. Company building/Plot L.R. No.
  9. Finally, the county, district, locality, and street where the company is located.
Click on the Business Registration Service to access the Business Linking Option
Business Registration Service Option

How to Link a Business on Ecitizen Portal

1. Log in to the eCitizen Portal using your Id number and password. In case you do not have an account, you should create an eCitizen Account to enable you to access the service.

2. After successful login, locate the Business Registration Services option and click on it.

3. Next to my Businesses Option, click on ‘link a business’.

Click on the Link a Business Option
Link a Business Option

4. On the find a business search bar provided, type the name of the business you want to link and click search. If you have typed the name or business registration number well, the name with the business number will appear with the status not verified at the end. Search by name as the registration numbers may differ from what you have.

Type the name of the business you want to link here and click on search.
Searching for the Business you Want to Link

5. Select the business that matches yours and click on next to continue.

6. Edit Details – Check if you need to edit any of the given details. These are the Business Name, Registration Number, Registration Type, and Registration Date. Compare these details with the ones provided on the certificate. Only edit these details if necessary, otherwise, skip to the next step. Click on Save and continue.

7. Nature of Business – Select the capacity of the person making the application and while on that select the nature of the business.

Link a Business Required Information

8. Registered Office Addresses – Capture the Primary Address of the business. This should be the information regarding where the business is located.

9. Ownership Information – Edit the ownership information using the provided button. Select the designation, and citizenship, enter the ID number, and first name, and then click on the verify button. Complete the rest of the form. If there are other proprietors follow the same procedure to add them. After adding the owner details, click on the save and continue button.

10. Click on submit and review.

You are Through with Business Linking Process

The process is complete and there are no charges for linking your business on the eCitizen Portal. After linking you have to wait for Officials from Sheria House to check what you have filled to approve or request an amendment if there is a problem.

However, if you need the linking urgently, you can print the reference number provided and visit Sheria House personally. The officials will see to it and approve the linking process.

Business Linking Approved

  • After approval, there is nothing to print. The status on the BRS page under my businesses area will read “active”.
  • Also, note that once approved, the Entity will appear as a verified and published entity in each of the directors, director-shareholders and or company secretaries’ accounts by default.
  • Any of the above upon logging in to their eCitizen account will be able to see the active business by clicking on BUSINESSES in their menu.
  • Clicking View against the Active Status allows you to enter and view the business account where you can maintain your accompany as you wish e.g., File for changes, Annual returns etc.

What You Can Do with a Linked Business

After successful linking, you can click on the view button to access more features. You can use these features to make some changes in your business. These changes found under Maintain Company option are;

  1. Cessation to convert – This option is found on business names. It is for converting a business name to a limited company.
  2. Cessation to close – This option is for closing/dissolving the business name.
  3. Change business particulars – This option will help you to change the business name.
  4. Under the Access Control option, you can be able to add a user.
  5. Finally, if it is a limited company, you can be able to apply for the CR12 form.

How do I Ensure my Business Linking is Approved?

Make sure you provide the details of the proprietors. If the business is registered with two or more individuals, provide their required details. Providing wrong information will prolong the approval period.

How to Update the Beneficial Ownership for a Limited Company

Limited Company owners are required by law to update details of legal ownership. This process is done through the eCitizen portal.

Kenya introduced section 93A of the Companies Act of 2015 in July 2019, through the Statute Law (Miscellaneous Amendments) Act.

This act states that all companies incorporated or registered in Kenya must keep a register of beneficial owners containing relevant information relating to such owners.

Definition of Beneficial Owner

Beneficial Ownership for a Limited Company
Beneficial Ownership for a Limited Company

The Companies Act defines a beneficial owner as “the natural person who ultimately owns or controls a legal person or arrangements or a natural person on whose behalf transactions are conducted, and include persons who exercise ultimate effective control over a legal person or arrangement.”

Under The Regulations, A Beneficial Owner Is A Natural Person Who Directly Or Indirectly:

  • Holds at least ten percent (10%) of the issued shares of the company;
  • Exercises at least ten percent (10%) of the voting rights in the company;
  • Holds the right to appoint or remove a director of a company; or
  • Exercises significant influence or control over a company.
Beneficial Owners
Maintain a company

According to the regulations, significant influence or control means ‘participation in the finances or financial policies of the company’.

For new companies, the process is already included and done during registration. Thus it is only a requirement for companies created before the introduction of this act.

Change of Officials
Beneficial owners

Those Who Can Update This Information

  • The Director
  • Director Shareholder
  • Company Secretary
  • Authorized Persons (must be added under Access Control )

The Prerequisite for updating beneficial ownership details is that the company must have been linked and appear as active under “My Businesses” as described above.

How to Update the Beneficial Ownership Information

  • Log into your eCitizen account
  • Click on the view button to access more details of the linked company.
  • Click on Maintain a Company on the left-hand side. On the right-hand side click on Beneficial Owners.
  • Click on Change Particulars at the top right-hand side and select Change of Officials (companies). A list of all the principals of the company is displayed.
  • On the list against each name is a blue button labelled ‘Update B.O’. Click on this button to update the said official.
  • A form that prompts the user to fill in the information is displayed.
  • Once you have successfully updated the BO information for each official you will be prompted to download, sign, scan and upload the Register of Beneficial Owners Form BOF1.
  • Confirm that the information provided is correct and click finish.
  • The BO information update will be submitted for review and approval by the Companies Registry Officers.
  • Keep checking your eCitizen account to see if the process has been successful.
Update Beneficial Owners
Update Beneficial Owners

Note that the system is configured in such a way that you must allocate 100% of the issued shares and 100% of the voting rights before proceeding to the next step.

A shareholder who holds less than 10% of the issued shares and voting rights and does not have a right to appoint a Director or have significant influence/control over the Company shall be disregarded for beneficial ownership disclosure purposes.

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