Peripheral Devices SS1 Computer Hardware & GSM Repair Lesson Note

What is a Peripheral Device?

A peripheral is any device that connects to the computer to help it do more. They are usually plugged into the “ports” (the holes on the side or back of the computer) or connected via Bluetooth.

We group them into three types:

1. Input Peripherals: They send information into the computer (e.g., Scanners).
2. Output Peripherals: They bring information out to us (e.g., Printers and Projectors).
3. Storage Peripherals: They hold information outside the computer (e.g., External Hard Drives).

The Printer (Making it Real)

The printer is the most popular output peripheral. It takes digital text or images from your screen and puts them onto physical paper. This is called a “Hard Copy.”

Common Types of Printers:

• Inkjet Printers: These use liquid ink. They are great for printing colorful photos at home.
• Laser Printers: These use a dry powder called “Toner.” They are very fast and are mostly used in offices or schools for printing many pages of black-and-white text.

Function: To create physical documents, receipts, or photos.

The Scanner (The Digital Photocopier)

If a printer puts things onto paper, a Scanner does the exact opposite. It “looks” at a physical paper or photo and creates a digital version of it inside the computer.

How it works: You place your document on the glass bed, a light slides across it, and a “picture” of that document appears on your monitor. This is called Digitizing.

Function: To convert physical documents into digital files (like PDFs or JPEGs) so you can email them or save them on your phone.

The Projector (The Big Screen)

A projector is like a giant monitor. It takes the image from a small computer screen and shines it onto a wall or a large white cloth using a very bright light and a lens.

Why do we use them?

• Presentations: So a whole classroom of students can see what the teacher is doing.
• Cinema: To watch movies on a massive scale.
• Church/Events: To show song lyrics or notices to a large crowd.

Function: To display computer images on a large surface for many people to see at once.

Keeping Your Tools Alive (Maintenance)

Peripherals are expensive, and in Nigeria, dust and heat are their biggest enemies. If you don’t maintain them, they will break quickly.

General Maintenance Tips:

1. Dusting: Use a soft, dry cloth to wipe your printer and projector lenses. Dust can scratch the glass of a scanner or block the cooling fan of a projector.
2. Covering: Always cover your printer with a cloth or plastic cover when you are not using it to keep dust out of the internal rollers.
3. Power Protection: Always use a Stabilizer or UPS. Sudden power cuts or “high voltage” can fry the sensitive circuits inside these devices.
4. Use it or Lose it: For Inkjet printers, try to print at least one page every week. If you leave it for months, the liquid ink inside the “print head” will dry up and block it.
5. Proper Shutdown: Never just pull the plug on a projector. It has a lamp that gets very hot; it needs its fan to run for a minute after you turn it off to cool down properly.

Quick Check!

• If you want to send your birth certificate to a school in another country via email, which device do you need?
• Why is a “Hard Copy” different from a “Soft Copy”?
• What is the best way to protect your printer from dust in a sandy environment?