Music and Licenses
Having the right music for your project is a hugely important element of your production. Picking the right song to evoke the emotion you want can leave the audience laughing or crying. Be sure that you match the tone of the music to the style of your project. Thriller films will benefit from more heightened music than a comedy, for instance. There are audio libraries that you can pull royalty-free music from and others that you need to purchase licenses for when it comes to music options. If you purchase a license, be sure that you buy the correct one for your intended distribution medium.
Consult your audio technician about any legalities for the music you're using before you start locking your edit to the music you're choosing. Hiring a composer to create original music for your project is the best way to ensure you can distribute your project with the music intact.