Weird characters appear when pressing command-A,C,V I'm not using Mac keyboard however it did work properly before. I changed the Command key to Ctrl. Until today, using this Ctrl key yield extremely odd characters. When pressing 


Ctrl-A yields å
Ctrl-V yields √
Ctrl-C yields ç


And I have no idea where these characters come from? So how could I fix this issue? Can anyone please help? Thanks.

EDIT
Here is my screenshot
It looks like you have accidentally configured your control key to be your alt key. Case in point: when I press alt+a, I get å. alt+v returns √, and alt+c gives us ç. Go into your settings and check again. They are located in System Preferences -> Keyboard -> Modifier Keys. Note: alt is also option.

Edit: I cannot duplicate this phenomena (see comments on this answer), so I will guess that the non-Apple keyboard is messing up the process somehow.