Definition: Images and videos can be compressed to save space. If too much compression is used on JPEG images, then small squares start appearing- this is called pixellation. This is an artifact of the compression process which throws away data. Up to a certain point, the lost data isn't noticeable but eventually pixellation begins.
Glossary:
A B C D E F G H I J K L M N O P Q R S T U V W X Y ZExamples:
TV Companies sometimes use pixellation to hide car number plates and faces on TV news or documentaries.

