Year 10 Computer Science - End of Year Quiz

The purpose of data compression is to decrease file sizes .

• True
• False

ASCII only contains English characters. The name of the system, which was was invented to represent other languages (such as Russian, Arabic or Chinese), and allows up to 1 114 112 possible characters is:

• Unity

• Unicode

• ANSI

• AlphCode

Why do computers work with binary bits instead of using decimals?

• Because computers can only understand the numbers 0 and 1

• Computers can not understand any numbers, however they understand on or off (or low voltage and high voltage) which they translate to on and off.

• Computers don't need binary, they can communicate using decimal numbers just fine.

• Because the people that first set up computers thought it would be easier to just program them using binary.

Lossless data compression usually works by..

• Finding repeating patterns.

• Deleting random bits data

• Removing data that is similar to others and hence won't be missed.

Data compression is important for websites because:

• Your webpage will load faster
• Compressed images look better

Computer users see images, text and graphics that have been converted from binary code

• True
• False

Which compression method makes the file smaller by deleting parts of the file permanently (forever)

• Lossy Compression

• Lossless Compression

Makes the file smaller by giving repeated patterns/colours a specific code

• Lossy Compression
• Lossless Compression

A set of instructions for the computer to follow

• Algorithm
• Iteration

What would you use compression for?

• Making an image file smaller
• Modifying an image