We construct a complete invariant for surface flows of finite type. In fact, although the set of topological equivalence classes of minimal flows (resp. Denjoy flows) on a torus is uncountable, we enumerate the set of topological equivalence classes of flows with at most finitely many limit cycles but without Q-sets and non-degenerate singular points on a compact surface using finite labelled graphs. To enumerate such flows, we describe properties of border points of a flow without degenerate singular points on a compact surface. In particular, we show that each connected component of the complement of the "saddle connection diagram" is either an open disk, an open annulus, a torus, a Klein bottle, an open Möbius band, or an open essential subset. Moreover, we generalize the Poincaré-Bendixson theorem for a flow with arbitrarily many singular points on a compact surface. In fact, the ω-limit set of any nonclosed orbit is either a nowhere dense subset of singular points, a limit cycle, a limit "quasi-circuit", a locally dense Q-set, or a "quasi-Q-set". In addition, for such a surface flow, we characterize the necessary and sufficient conditions for the closure of the union of closed orbits corresponding to the non-wandering set.