Canopy Question

While browsing some pictures of the Rafale, I got to wondering about the canopy designs on modern combat aircraft. Why is it that some open upward (F-14/15/16/18/22/35) and others open to the side (Rafale, Gripen, Typhoon)? Is this just a design quirk is is there a reason why the designers feel one is better than the other?

Thanks!