USB Flash Drives

What are USB Flash Drives?

Small portable devices that plug into the computer

What are USB Flash Drives used for?

Used to transfer data from one device to another

What is good about USB Flash Drives?

Very fast

Portable

What is not so good about USB Flash Drives?

Limited capacity

What is inside the USB Flash drive?

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How do USB Flash drives work? ?

Initialise

• Put drive into USB socket
• USB driver loads
• providing the computer with code on how to read and write
• The USB is read, giving information on the file and folder structure
• This is called the File Allocation Table (FAT)

Reading

• The user chooses to open a file
• the Computer sends the address wanted to the USB port
• The USB returns the data at the location requested

Writing

• The computer sends data to the USB port
• where it is place into empty space on the drive
• The computer then requests a new version of the FAT

Lots of cool USB flash drives

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Exam Question!!!

1. How does a computer write to USB?

2. What is an advantage of a USB flash drive?

3. What is a disadvantage of a USB flash drive?

4. What is an example of an use of a USB flash drive?

ANswers!!

Writing

• The computer sends data to the USB port
• where it is place into empty space on the drive (1)
• The computer then requests a new version of the FAT (1)

Advantage

• Very Fast
• OR
• Portable

DISAdvantage

• Expensive per MB compared to hard drives
• OR
• Limited capacity

USE

• To transfer data between devices