The different types of variations distributed in continuum is referred to as the continuous variation in genetics. The example might be our height and weight. It ranges from that of the shortest person in the world to that of the tallest person. Any height is possible between these values. So it is continuous variation.

The different types of variations that are placed into discrete values as in individual categories are referred as discontinuous variation. Example might be human blood group since there are only 4 types available - that is either it can be A, B, AB or O ; nothing in between. Another example might be Sextype - it can be male, female or transgender.

Hope you understood. Thank-you.