Biryani and pulao are both rice dishes with meat or vegetables and whole spices, and they are frequently confused. The methods are structurally opposite, and everything else follows.
Pulao is an absorption method
In a pulao, the rice is fried briefly with aromatics and then cooked in a measured amount of liquid, which it absorbs completely.
Because all the liquid ends up inside the grains, whatever flavor is in that liquid distributes evenly through the dish. Every spoonful tastes essentially the same.
The measured-liquid rule is what makes pulao a single-vessel dish that a home cook can execute reliably. The proportion of water to rice is the main variable.
Biryani is a layering method
Biryani cooks the rice separately in abundant water and drains it while still underdone, and cooks the meat or vegetable component separately in its own gravy.
The two are then layered in one vessel and finished together with the pot sealed, so steam trapped inside completes the rice while flavor moves upward from the gravy below.
Because the components meet late, the dish retains distinct zones. The bottom is saturated and intensely flavored, the top is comparatively plain, and mixing at the table is part of eating it.
The rice is treated differently for a reason
Draining rice at partial doneness removes surface starch, which keeps grains separate and lets them finish in steam without turning sticky.
Pulao's absorption method leaves that starch in the pot, which is acceptable because the grains are meant to be tender and lightly clinging rather than fully individual.
The sealed finish is not decorative
Sealing the vessel keeps steam inside at a low, even heat, which is what cooks the top layer of rice without any liquid being added to it.
Traditionally the seal is a rope of dough around the lid, and modern kitchens use a tight lid with a weight or foil. Either way, the point is that no steam escapes.
What this means for cooking either at home
Pulao is the more forgiving dish and suits a weeknight, since it is one pot and one timing decision. Biryani requires two separate cooks and a controlled finish.
Long-grain aged basmati matters more for biryani, where separate grains are the goal, than for pulao. American supermarkets stock basmati widely, and Indian grocers carry aged varieties that behave more predictably.