Prefixes are letters added to the beginning of words to form new words. The prefix tele, which comes from the Greek word for 'at a distance' is found in many words.

telephone

television

Suffixes are letters added to the end of words to form new words. The suffix phone comes from the Greek word for 'sound'.

telephone

microphone

When you learn the meanings of word roots, it enables you to understand the meaning of other words.