Using Point as the geom type in pgrouting?

in my table i have the field geom(POINT, srid) and its populated, this table also have the source an target field witch is blank(just like pgrouting guide).

I tried the function pgr_createTopology() and it returns ok, created the vertex_pgr table but it is empty.

Must the geom field be a geom(LINESTRING)?

My problem is: i have some points and need to trace routes between them.

Do i have to make line string between my points?