The "80 PLUS" certification is a program that promotes energy efficiency in power supplies for computers and other electronic devices. It ensures that a power supply unit (PSU) operates at a minimum efficiency of 80% at various load levels, which helps reduce electricity consumption and heat generation. This certification is important for users looking to save on energy costs and minimize their environmental impact. There are several tiers of the 80 PLUS certification, including 80 PLUS Bronze, 80 PLUS Silver, 80 PLUS Gold, 80 PLUS Platinum, and 80 PLUS Titanium. Each tier represents higher efficiency levels, with 80 PLUS Titanium being the most efficient. Choosing a certified PSU can lead to better performance and longevity for computer systems.