Reciprocal pronouns are used when two or more people or things are doing the same thing, and experiencing the same consequences. The reciprocal pronouns are each other and one another.
Each other is used when there are only two people.
The boys made rude sounds and laughed at each other.
Shake hands with each other and make up.
One another is an indefinite reflexive pronoun which is used when there are three or more people, or when it’s unclear how many people will be involved.
At Christmas, people give gifts to one another.
Love one another.