Cloud sync tools (Dropbox, Google Drive, OneDrive) feel like backups because your files exist somewhere else — but sync and backup are different concepts, and the difference matters exactly when something goes wrong.
Sync tools mirror changes in near-real-time, which means if a file gets corrupted, ransomware-encrypted, or accidentally deleted locally, that same change often syncs to the cloud copy too, sometimes within seconds. A true backup takes point-in-time snapshots you can roll back to, specifically so a bad change doesn't destroy every copy simultaneously.
Scheduled, versioned snapshots that let you restore to a specific point in time — not just "the current synced state" — plus full system image backups that let you restore an entire machine, not just individual files, if a drive fails completely.
For casual personal use with low-stakes files, sync's convenience may outweigh the gap — the risk is real but the consequences of hitting it are manageable. For business data, financial records, or anything genuinely irreplaceable, that gap is the entire reason backup software exists as a separate category.
Sync for convenience and access across devices, dedicated backup software for actual disaster recovery — running both isn't redundant, they're covering different failure modes.
