Is crystal meth the same as regularly prescribed methamphetamine?

I've been taking methamphetamine for about 9 years. It's like a strong strong cup of coffee. If methamphetamine is the same as crystal meth, I just don't get why they steal and rob for such drug.

I can go without methamphetamine for many days, the result will just cause me to be a bit slower in thought. Is crystal meth the same as methamphetamine or is this a claim from people that know nothing about the two drugs.

Please help me to understand.

Thanks.

: http://alcoholdrugstreatment.info/is-crystal-meth-the-same-as-regularly-prescribed-methamphetamine