Windows 10 launched in 2015 as Microsoft's successor to Windows 8.1, and its log on chime became one of the most heard system sounds of the following decade as the operating system spread to hundreds of millions of PCs. Unlike a harsh error sound, the tone was designed to feel welcoming at startup. Clips of the sound are now shared outside Windows for tutorials, parodies, and nostalgia edits, often paired with a simple ding sound effect for other on-screen prompts, because the login moment is familiar even to viewers who have moved to newer systems.