Consequently, the default install of most distributions offer a less than stellar level of performance when installed on older hardware.

因此，在较老的硬件上默认安装大多数发行版时，提供的性能都不是一流的。

youdao

The default setting allows you to install apps from the Mac App Store and apps from developers that have a unique Developer ID from Apple.

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By default, Mountain Lion will only let you install programs carrying these certificates.

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That means that the YouTube app, the previous version of which was created by Apple, no longer will be a default app on the devices, so people will have to manually install it.

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