The phrase "intellectual property" hides four separate legal systems—copyright, trademark, patent, and trade secret—each grounded in a different statute, each protecting a different kind of asset, each arising in a different way, each lasting a different length of time, and each tested for infringement by a different question. Owners confuse them at real cost: the founder who "copyrights" a brand, the engineer who thinks writing code down patents his algorithm, the company that calls a shared spreadsheet a trade secret. This guide sets the four regimes on one table across six axes—subject matter, source of the right, term, registration, the infringement test, and remedies—anchored in the Copyright Act, the Lanham Act, the Patent Act, and the Defend Trade Secrets Act. It then explains the constitutional architecture that makes two regimes expire and two run forever, and the "channeling" doctrine that keeps each in its lane, drawing on Baker v. Selden, Sears/Compco, Kewanee Oil, TrafFix, and Dastar. A worked example threads one invented product—a countertop fermentation appliance—through all four protections at once, and a decision framework, FAQ, and cross-referenced companion guides show owners how to map every intangible asset to the right tool before a dispute rather than after.