The Standard Dust Models (Λ=0)
This is easy to interpret.
When Ω0 < 1, universe is open, hyperbolic, and expands to infinity
with finite velocity.
When Ω0 > 1, universe is closed, spherical, and eventually collapse
after reaching a maximum size after a time:
Recollapses after a time t = 2 tmax.
When Ω0 = 1, universe is critical, flat, and expands to infinity with
velocity approaching zero.  Einstein-de Sitter model: