The Portal Gun is your sole and most powerful piece of equipment. It allows you to create two interconnected portals, one blue and one orange, on specific white surfaces. Its functionality is the cornerstone of all puzzles in Portal. You acquire it in two stages: first, a single-portal version in Test Chamber 01, and then the full two-portal version in Test Chamber 03. Mastering its use involves understanding momentum conservation, portal placement angles, and quick portal switching. There are no upgrades for the Portal Gun itself; its capabilities remain constant. Your skill with it, however, will grow exponentially as you progress through the game. It's not just a tool; it's an extension of your problem-solving mind.
