Meaning of the word "chalk and cheese" in English

What does "chalk and cheese" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

chalk and cheese

US /tʃɔːk ənd tʃiːz/
UK /tʃɔːk ənd tʃiːz/

Idiom

two things that are completely different from each other

Example:
My brother and I are like chalk and cheese; he loves sports, and I prefer reading.
Their personalities are chalk and cheese, yet they are best friends.