A USB audio interface in the missing link between your instrument and your computer. It is the most cost effective way to begin building your home studio. Often coming with dual inputs to record guitar and/or vocals simultaneously. It is perfect for singer/songwriters to record separate tracks and edit them accordingly.
Most USB audio interface's come with "Recording Software" which will get you started straight out of the box, but there is also plenty of free software to find on the internet.
USB Audio interfaces are a must for any budding musician wanting to get started on building a home studio and recording their first tracks.