The location of the ovary in relation to the other flower parts is a key feature used to identify a flower species. There are three examples given below.

Geranium flower superior ovary
Daffodil flower inferior ovary
                                                                                                                     

The first photo shows a Superior ovary. The sepals, petals and stamens arise from below the ovary.This is the commonest type of ovary. The flower is technically Hypogynous where hypo means flower parts start ‘below’ the ovary.

The second photo shows an Inferior ovary. The tepals, corolla tube and stamens (filaments plus anthers)arise from above the ovary. The flower is technically Epigynous where epi means ‘above’

There is one type of Superior ovary that appears to be inferior.  The flower parts arise from the rim of a hypanthium – a cup shaped extension of the base which encloses the ovary. Imagine the hypanthium to be a flat ring and you can see that the flower parts actually arise from below the ovary. The flower is technically Perigynous where peri means ‘around’. Typical of the Rose family.
Cherry flower superior ovary