1.2 Data Compression

What is compression?

• To convert one file to another
• To reduce the size of data to save space
• To minimise the time taken for a file to be download
• To compress something by pressing it hard

What does Lossy Compression do to files?

• Increases the file size and keeps the same quality
• Eliminates no information at all
• Decreases the file size and keeps the same quality
• Eliminates unnecessary information in a file to reduce file size

What is Lossless Compression?

• No information is lost but file size is increased
• There is no loss of information at all after compression
• Files which have the exact same data after compression
• Compression involves an algorithm

What type of compression would you use to compress a video?

• Lossy
• Lossless

What type of compression would you use to compress a text file?

• Lossy
• Lossless

When Lossy compression is used data is lost?

• True
• False

Which of the following are not in a compressed format?

• JPEG
• MPEG
• Bitmap
• MP3

What would you use compression for?

• Making an image file smaller
• Modifying an image 

Compression in general makes it _______ to send, upload and stream data

• Quicker

• Slower

Lossless compression permanently deletes the data

• True

• False