To get the latest features and maintain the security, stability, compatibility, and performance of your Mac, it's important to keep your software up to date. Apple recommends that you always use the latest macOS that is compatible with your Mac.
Mac operating system’s twelfth major version is the El Capitan Installer (version 10.11). All the Mac computers which don’t have the privilege to upgrade to MacOS High Sierra or the computers that need to upgrade to El Capitan first, can download this twelfth version on the computer. The Direct Download Links of OS X El Capitan 10.11.5 Final Setup / Delta / Combo Update Installer.DMG Files are also available below for manual installation using iTunes. Apple has brought many useful changes with addition of new functionalities in OS X 10.11.5 Update, which you can read in image below.
Learn how to upgrade to macOS Big Sur, the latest version of macOS.
The version of macOS that came with your Mac is the earliest version it can use. For example, if your Mac came with macOS Big Sur, it will not accept installation of macOS Catalina or earlier.
If a macOS can't be used on your Mac, the App Store or installer will let you know. For example, it might say that it's not compatible with this device or is too old to be opened on this version of macOS. To confirm compatibility before downloading, check the minimum hardware requirements:
Safari uses these links to find the old installers in the App Store. After downloading from the App Store, the installer opens automatically.
Safari downloads the following older installers as a disk image named InstallOS.dmg or InstallMacOSX.dmg. Open the disk image, then open the .pkg installer inside the disk image. It installs an app named Install [Version Name]. Open that app from your Applications folder to begin installing the operating system.