Q: OSX Yosemite 10.10.4 and iCloud Drive

Not sure if this happened under the previous incarnations of OS X but i find that there is now an addition of iCloud Drive when opening Finder.

I wouldn't object if this was only showing my cloud storage but when i checked it also eats into my hard drive storage.

I copied all my files (photo, music etc) on my iMac to the iCloud Drive but then i opened my Macbook Air.

It took for ever to load and was very slow and to my amazement the files in iCloud Drive were being downloaded to my Air (with only 64Gb storage it very soon had nothing left).

Turning off iCloud on the Air resolve ihe problem and cleared the downloaded files, eventually, but if means I cannot access my files in the cloud on my Air

Is there anything I can do to resolve the problem? I have a sneaky feeling that iTunes may do the same thing so am reluctant to try opening that as well.

I was expecting to just see all the files as I do on my iPad not for them to be downloaded to the Air.

Anyone have any ideas?