What is a Sole Proprietorship?
A business associated only with you is known as a Sole Proprietorship.
You may operate a sole proprietorship using your own legal name or your name plus some descriptive words or a completely unique business name. If you use any name other than your legal name, you must register this assumed business name with the government.
If you will operate under your legal name, but want to open a business bank account, the bank will often require you to register that name anyhow. If you wish to operate this way, inquire with your bank branch for details. Alberta, BC and Saskatchewan do not let you register just your own name. They make ask you to add a descriptive term.