Queries on using Apple GarageBand

Hello Experts!
I have a simple query about GarageBand of Apple. And I hope that you will not use too technical words in stating your replies, as I am not very techy person and I only know a little about technology. Here are my questions:
a) How do I transfer my GarageBand in a storage device?
b) When I played my garage band recording using my headphones or my iPad, it played smoothly. But when I attached it into an email and tried sending it to myself, a high frequency sound was emitted in the recording.
How did it happen?
Thank you in advance.
