What is the codename of the protagonist in the original Metal Gear Solid?

The protagonist of the original Metal Gear Solid is codenamed Solid Snake.

Solid Snake is a legendary former soldier and infiltration specialist who is sent to Shadow Moses Island during the 1998 game. His mission is to stop FOXHOUND, rescue hostages, and prevent the nuclear-capable Metal Gear REX from being used.

The name can be confusing because the series includes several related Snake characters. Liquid Snake is Solid Snake’s genetically engineered brother and the leader of the Shadow Moses terrorist group. Naked Snake is the identity later associated with Big Boss, while Venom Snake is a separate character portrayed as Big Boss in Metal Gear Solid V. Solid Snake himself is the central playable character in the first Metal Gear Solid and returns in later entries, including Metal Gear Solid 2 and Metal Gear Solid 4.