Unlike modern consumer electronics that receive over-the-air updates, arcade machines have traditionally required physical intervention for software and firmware modifications. The primary method throughout arcade history has been the replacement of entire circuit boards or ROM (Read-Only Memory) chips. Game developers would ship new versions of a game on dedicated PCBs (Printed Circuit Boards), which arcade operators would physically swap out with the old ones. This was necessary because the original hardware was often designed for a single, unchangeable purpose.

For smaller updates or bug fixes, technicians would replace specific ROM chips on the existing board. This process required technical skill and the correct equipment. The standardized JAMMA (Japan Amusement Machinery Manufacturers Association) wiring harness helped streamline this process by creating a universal connector for different game boards.

In modern times, some arcade machines, especially those connected to networks, can receive digital updates. These contemporary systems may download patches and new content directly to an internal storage device, similar to how home consoles operate. This is common for redemption games, prize dispensers, and large-scale linked arcade experiences. However, even these networked updates are often carefully managed and deployed by technicians to ensure stability.

A significant challenge in the arcade ecosystem is preserving the original software state of classic games. Updates were not always documented, leading to multiple versions of the same game with subtle differences in gameplay or difficulty. Today, security is also a concern; networked machines require firmware updates to protect against vulnerabilities, just like any other connected device. Ultimately, the method of update depends heavily on the machine's era, with physical hardware swaps defining the classic arcade era and cautious digital updates becoming more prevalent in modern, connected cabinets.