Git USES an internal index to track the state of the files and directories in a repository.

Git使用内部索引跟踪文件的状态和存储库中的目录。

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ETFs are quoted securities that track a particular index, for a fee that is normally just a fraction of a percentage point.

ETFs是跟踪某种特殊指数进展的上市证券。它的费用通常不到百分之一。

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Index funds track the performance of markets and charge very low fees.

FORBES: Earn 2 Percent More in 3 Easy Steps

Motif Investing has put together a motif index to track rebuilding efforts along the path of the storm called Rebuilding After Sandy.

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If you invest in single asset class index funds like the Vanguard Total US Stock Market index or the Spartan International Index at Fidelity, you can easily compare the performance of your individual holdings to the market index they track.

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