MetaFiler takes advantage of some of the more advanced features of the NTFS file system. NTFS supports what are known as Named Streams. Named Streams are separate data associated with a traditional file.

Microsoft use Named Streams to allow Macintosh Resource Forks to be saved and served using Windows Services for Macintosh (SFM). Because Named Streams are invisible to most applications, Windows users can see the same files as Macintosh users while Macintosh users get the features they need for their platform.

Microsoft also use Named Streams for caching thumbnails in the Explorer Thumbnail view. This means that thumbnails only ever need to be generated once instead of every time you view the file.

Unfortunately some of the APIs for accessing Named Streams are complicated, fairly low level and badly documented - something which has always limited adoption. However MetaFiler hides all these complications for you and just lets you get on with what you want to do.

Because Named Streams are essential for Windows, Microsoft has ensured that products work properly with them wherever it's necessary. So although you may not be able to see Named Streams, when you copy files from one place to another the streams will go with the file. Similarly, if you use backup software, all streams are backed up, not just the ones you can see.

Because MetaFiler is Unicode compliant throughout, you can use it with any language from English to Arabic to Korean.