What are the white and yellow numbers seen during combat?

There are several possible colors that may show up when damaging an enemy.

• White is the most common color, which indicates normal kinetic damage.
• Yellow indicates critical hits, which is often shown when shooting the critical spot of an enemy (Some enemies doesn't have this critical hit spot, like Fallen Shanks). Usually this is in the head of the enemy.
• Grey indicates "weak damage", which appears when you are significantly higher level than your enemy, you deal reduced damage. This is a mean of balancing the game for higher/lower leveled players/enemies.
• There's also the colors blue, orange/red, and purple, which indicates which elemental damage you inflict to the enemy. This is only effective when shooting the matching shield of an enemy.