Essential if you play across more than one PC
If you switch between a desktop and a laptop, or a home and an office PC, cloud saves let you resume from your last save point automatically. Without it turned on, progress made on one PC simply won't show up on another.
Not every game supports it
Cloud saves only work for titles the developer has specifically enabled for Steam Cloud, and support isn't universal. Check a game's Properties before assuming your save will carry over, especially for older or less common titles.
Frequently Asked Questions
Does every game support cloud saves?
No β only games the developer has enabled for Steam Cloud support it. Check the General tab in that game's Properties to see if it's available.
Is there a limit to how much I can store in the cloud?
Yes, each game gets its own allotted cloud storage from Steam, and syncing can stop working for that game once you exceed it.