Double-click the downloaded InstallOSX.dmg file to mount it. Open the mounted volume and double-click InstallOSX.pkg .
如果 Mac 已安装 Yosemite 早期版本（如 10.10、10.10.1 等），则无需重新安装整个系统。苹果官方提供了 （Combo Update），可将任何 10.10.x 版本直接升级至 10.10.5。 mac os x yosemite 1010 5 download dmg link
With a click, the download began. The progress bar crawled across the screen like a slow tide. When the finally landed in his downloads folder, it felt heavier than a mere sequence of bits. He mounted the disk image, the white icon appearing on his desktop like a digital peace offering. Double-click the downloaded InstallOSX
Download OS X Yosemite via Apple Support mac os x yosemite 1010 5 download dmg link