Kun: it’s used by people of senior status in addressing or referring to those of junior status, or by anyone when addressing or referring to male children or male teenagers, or among male friends. It can also be used by females when addressing a male that they are emotionally attached to or have known for a long period of time.
Chan: it’s a diminutive suffix; it expresses that the speaker finds a person endearing. It’s used for teenagers, cute animals, lovers, close friends, any youthful woman, or between friends.
Senpai: it’s used to address or refer to one’s senior colleagues at school, at work, etc.
Kouhai: it’s a junior, the antonym of senpai, but it is not normally used as an honorific; kun is used for this function instead.
San: it’s the most commonplace honorific, and it’s a title of respect typically used between equals of any age. Although the closest analog in English are the honorifics ‘Mr.,’ ‘Miss,’ ‘Mrs.,’ or ‘Ms.,’ ‘san’ is almost universally added to a person’s name, in both formal and informal contexts.
Sensei: it’s used to refer to or address teachers, doctors, politicians, lawyers, and other authoritative figures.
Sama: it’s a markedly more respectful version of san. It is used mainly to refer to people much higher in rank than oneself, toward one’s guests or customers (e.g., a sports venue announcer addressing members of the audience), and sometimes toward people one greatly admires.