As per I know- The two types of orchids are terrestrial orchids and epiphytes.

Terrestrial orchids include orchid species that grow on the ground. Epiphytes are orchid species that grow in trees.

Both terrestrials and epiphytes can grow in one of two ways - new shoots can appear alongside the original growth causing the orchid to spread, or new growth can be added to the apex which increases the height of the orchid.