A relation is a connection between 2 elements in a set or between 2 elements in 2 sets. Consider a set of family members {Ngale, Efeti, Eyanga, Manga, Eposi}. Suppose Ngala is 12 years old, Efeti is 10 years old, Eyanga is 8 years old, Manga is 6 years old, Eposi is 4 years old. We can make the following;

Eposi is younger than Manga, Manga is younger than Eyanga

That is having a relation R (is younger than)

Eposi                     Manga

Manga                 Eyanga

Eyanga                 Efeti

Efeti                      Ngale

                                                                   Eposi

                                            Ngale

Manga

                                                             Efeti

                                                                                   Eyanga