Microsoft has integrated SkyDrive more deeply into Windows 8.1. Welcome Placeholder files, new kind of shortcut! When you agree to integrate SkyDrive with Windows 8.1, you’re given “access to all your SkyDrive files without actually downloading them, using precious local disk space and Internet bandwidth. Placeholder files look and feel like normal folders and files. You can tap or click a folder and see all the folders and files inside it. You can tap or click a file and it will open, you can edit it and close it. You can move, delete, copy, or rename placeholder files just like you would any folder or file. But [Windows] only downloads the full file when you access it.”
The advantage? Huge space savings: 5 GB of used space in SkyDrive can take up less than 150 GB on the local disk, for example.
More features:
Smart thumbnails. When you flip through photos, [Windows] downloads large thumbnail images instead of the actual files. And [Windows] pre-fetches thumbnails to enable fast scrolling. It’s only when you want to edit a photo that [Windows] downloads the full file to the local disk.
Offline access. Make available offline” from the pop-up menu that appears. But this works from the SkyDrive app too, so tablet users and others that wish to avoid the desktop never need to leave Metro to access this functionality.
File open and save. SkyDrive is built into the Metro-based File Picker experience as well as File Open and File Save on the desktop side, so you will be able to access your SkyDrive-based files, and save to SkyDrive, from any Metro app or desktop application.
Search. SkyDrive is also built into the new Smart Search experience in Windows 8.1, and SkyDrive files show up in search results just like your local files.
Source: Microsoft