Eagle

Eagle (acquired by the massive CAD titan Autodesk and integrated into Fusion 360) is a fiercely powerful, highly historic, and deeply beloved platform. It operates as the absolute, heavy-weight king of "Maker-Movement and Mid-Tier PCB Design." Long before Altium dominated the enterprise, Eagle built a massive global empire by being the accessible, highly scriptable default software for the open-source hardware community (Arduino, Adafruit). The absolute core differentiator of Eagle is its "Massive Open-Source Component Library and Fusion 360 Integration." Because the entire open-source world used Eagle for 20 years, literally millions of free, mathematically perfect component footprints (parts) are available to download. Now backed by Autodesk, Eagle mathematically integrates flawlessly into Fusion 360, allowing seamless mechanical and electrical co-design. Because it completely democratized access to highly professional PCB layout tools, offering unparalleled community libraries, deep Autodesk mechanical integration, and highly accessible pricing, it is heavily favored by hardware startups, massive university engineering programs, and serious hobbyists.