The DMCA (Digital Millennium Copyright Act) is a US law that makes it illegal to bypass digital locks on copyrighted content — even if you own the content. Think of it as a law that protects the lock, not just the thing behind the lock. This is the disconnect that confuses people.
The DMCA has two main parts: (1) it forbids circumventing copyright protection measures (like DRM on movies, ebooks, or games), and (2) it forbids trafficking in tools designed to circumvent those protections. You can own a DVD legally, but bypassing its copy protection to make a backup is technically illegal under the DMCA — even though you already paid for it.
The DMCA has been controversial for 25+ years because it shifts power to manufacturers: they can lock down devices you own, control what software runs on them, and prevent repairs or modifications. It also creates a chilling effect on security research — proving a lock is weak is illegal, so fewer people audit it.
Canada has its own version: the Digital Lock Provisions in the Copyright Act. It is similarly restrictive, though courts have been slightly more lenient on some circumvention activities (like format-shifting for personal use). The DMCA does NOT directly apply in Canada, but US law affects Canadian tech because many services (Netflix, Apple, Adobe) operate under US law.
Pro tip: If you are buying hardware or software, check the terms of service for DRM locks — they determine what you can legally do with your purchase. A $40 tool with no DRM gives you more actual ownership than a $400 device locked down with digital restrictions.