What are some examples of nucleotides?
Nucleotide really just means a component of a nucleic acid in which you have 3 components: Ribose sugar, Nitrogenous base, and Phosphate (if you are missing the phosphate, these are called nucleosides.
So you can have either DNA or RNA nucleotides. Take the adenosine base as an example. This can be either DNA or RNA, and it can contain 1/2/3 phosphate groups (mono/di/tri). If it has 3 phosphate groups and has ribose as its sugar, it is called ATP, adenosine triphosphate. If it has 1 phosphate and the deoxyribose sugar, it is called dAMP, deoxyAdenosine monophosphate.