This is a very good question, but not very easy to answer. Promise Rings can mean so many different things to different people. It all depends on the giver of the ring and the meaning he or she gives it.
But in almost all cases, it’s a symbol of commitment between two people. And those two people can be friends, lovers, family or in any other kind of relationship.
Often, it is the first official outing of committing the new relationship between two people who are deeply in love.
Tip: make it crystal clear to the person you give a Promise Ring to, what your meaning is by giving this ring. As you do not want him or her getting the wrong idea or false hope.