Software usability, a field that once focused solely on making digital systems easy to use, has expanded dramatically in scope and influence over the past several decades. Usability is no longer confined to simplifying interfaces—it now encompasses how users emotionally, cognitively, and physically interact with software across diverse devices and environments. As the digital world grows more complex, with emerging technologies such as artificial intelligence, augmented reality, and voice-based interfaces gaining traction, the usability challenges and opportunities continue to evolve.