If you're a professional musician, or an aspiring professional musician, you'll at some point need to be able to display what you do as a musician to prospective venues at which you'd like to perform. Musicians, just like any other business owner, need to keep their overhead low and profit margins high. It makes sense then that a musician needs to have their music recorded to easily allow potential venue owners to hear their sound hopefully leading to gig bookings.
But if you're getting started as a professional musician and you have a budget of basically zero dollars to allocate toward the recording of a demo. If that sounds like you then you'll want to keep reading.
There are several ways to record a decent demo for the purposes of getting gigs without breaking the bank.