What Is Their Main Difference?
The difference between 'anybody' and 'nobody' as pronouns is that 'anybody' is any one out of an indefinite number of persons, while 'nobody' is not any person. It is the logical negation of 'somebody'.
'Anybody' means any random person out of an indefinite number of persons. We use 'anybody' to address a group of several people, for example:
'Nobody' shows absence of a person. It works as a singular pronoun in sentences. Note that when we have 'nobody' in a sentence, the verb should not be in negative form.
anybody = any person
nobody = no person