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When first rolled out, Dropbox's synchronization program would only synchronize the entire contents of a single folder with an entire online repository. This synchronization work could become quite time-consuming, and also consume large amounts of storage space on the hard drive of the local device. The current app is much smarter, and works much more efficiently with the "SmartSync" feature enabled (Lehigh enables this by default). . LTS has set this feature to be enabled by default, and we recommend you leave it that way.
While it maintains a complete list of files and folders to sync, it leaves most data cloud-resident, and only stores local copies of recently-used files or those files for which you specify keeping one. This vastly reduces the syncing burden, and makes downloads transfers of files happen only as needed. With good network speeds, and users usually working on only a few files at a time, this is a much more efficient scheme.
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