If you want the ability to perform a fresh and clean install of macOS Sierra, then you should consider creating a macOS Sierra USB install disk. Not only will this walkthrough work for the macOS ...

For a long time, Microsoft didn’t sell Windows install media in the form of bootable USB flash drives. Instead, it prefered to stick to old-school DVD media, despite the fact that many notebooks today ...

OS X Mavericks is available in the Mac App Store now, but it's only an upgrade—but if you want to do a clean install, you'll need to manually burn an installation flash drive. Here's how to do it.