Inside every cell, millions of tiny machines, called proteins, tirelessly work to keep us alive. But understanding what these proteins do and where they go is a challenge. That's where protein labeling comes in. By attaching special tags, scientists can track proteins like detectives following a clue. These tags can glow, bind to specific molecules, or even be radioactive, revealing a protein's location, function, and interactions with others. Like a map lighting up a hidden city, protein labeling sheds light on the intricate workings of the cell, unlocking secrets of health, disease, and even the development of new drugs.