Error compiling for Arduino Gemma

wont connect or error saying "Error compiling for Arduino Gemma." and i don't know why?!

i don’t know why?!

We don’t either because you haven’t given even close to enough information. After there is an error you will see a button on the right side of the orange bar “Copy error message”. Click that button and then paste the error in a message here USING CODE TAGS(</> button on the toolbar).