SkyDrive provides 7GB for free. If you want to know current usage, open SkyDrive with browser and usage is shown at lower left corner of the page.
From SkyDrive Store App, open settings charm.
Current usage will be shown.
Clicking “Manage Storage” opens page with IE.
If you are running low in free space, you can purchase additional storage. Click “Get more storage” to see storage plans and prices.
By storing photo or files to SkyDrive, you can access to your files from any computer connected to internet, and also protects you from losing data if your HDD dies (HDD is a device with limited lifetime, will die eventually).
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