The Nathan Drake Collection remastered three main Uncharted games: Uncharted: Drake’s Fortune, Uncharted 2: Among Thieves, and Uncharted 3: Drake’s Deception.
The collection was designed as a single-player package for players moving from PlayStation 3 to PlayStation 4. Bluepoint Games rebuilt and enhanced the trilogy, improving textures, lighting, controls, aiming, camera behavior, and cutscenes.
A common mix-up is counting Uncharted: Golden Abyss, the PlayStation Vita spin-off. It was considered during development but was not included because its story was viewed as separate from the main trilogy. Uncharted 4 was also not part of the collection; it followed in 2016 as a separate PlayStation 4 release.
The package also omitted the original multiplayer modes from Uncharted 2 and Uncharted 3, containing only their story campaigns. That is why “three” refers to the remastered main games, not every Uncharted title released before 2015.