Wondering why you've got Photoshop CC and Photoshop CC 2014 on your computer? You're not alone.

Reactions to last week's big update to Adobe's Creative Cloud have been both positive and negative – and also perplexed. Previous updates to Photoshop CC et al have been traditional updates – ie they replace the application that's already on your machine with a version with a greater number of features and fewer bugs (or. sometimes, more bugs).

However, the updates installed last week were more like when Adobe went from CS6 to CC – or any previous major upgrade – in that new versions of the software were installed next to the previous versions, so you end up with both Illustrator CC and Illustrator CC 2014 in your Applications folder or Start Menu.

Why do I have Photoshop CC and Photoshop CC 2014?

The Creative Cloud 2014 update can leave you with many versions of Photoshop CC, Illustrator CC etc on your computer.

So why has Adobe done this? Surely this is just a waste of space – space you might need if you've only got a 256GB SSD on your laptop, for example. And for all Adobe's promises of a seamless upgrade process, I still had to change my UI and keyboard shortcut preferences – though to be fair each was a single click change – and reload my Crop tool presets in Photoshop.

Adobe has clarified that our initial assessment was correct – that the CC 2014 versions are different enough from the previous CC versions that running both side-by-side is wise – at least initially.

"Both version of the software are there to ensure maximum compatibility," an Adobe spokesperson told us in a statement. "If a user has a workflow that relies on some 3rd party software or service, they may not have updated their tools."

Photoshop CC 2014's Wacom problems

Some non-Adobe plugins and hardware drivers will need to be updated before being compatible – we've seen reports of problems with support for Wacom tablets on Windows 8.1 due to under-the-hood changes to support tablet computers such as the Microsoft Surface Pro 3.

There many also be other bugs that might make you want to stick with the old CC version. And if you like Photoshop's Oil Paint filter or want to run Creative Cloud tools on an OS X 10.6 Mac, you're gonna have to stick to the old version too.

We'll update this story when Adobe respond to our request for information.