Why do I have a different version than tutorials?

I just downloaded unity, the free version. So I go into tutorials and the version that is used there seems to be different. It’s not even the same color. I have Unity 5.1.0f3 (64-bit). The tutorial version is different and I can’t fallow the exact same steps. Trying the PROJECT: ROLL-A-BALL tutorial. I even uploaded the screenshot of my screen to this. His seems to be a different version, it is similar in most ways but some things are different. Do I have to buy something to have the same one?

The darker version of the editor mean that it’s the Pro version, the lighter skin is on Personal edition, there is no technical differences between these versions.

also, i’ts not mentioned until the 2nd and 3rd tutorials, but you can rearrange all of the windows to match the tutorial. (which i’m guessing is what you’re talking about).

Tried the layout button in the top right corner? Push a few to find the one the tutorial is using.

As to why versions are different in general, that’s normally because Unity is doing awesome upgrades all the time. Keeping the tutorials up to date is a never ending challenge.