Not everyone has access recording studio software on their computer (although there are some pretty good ones like Audacity).
Soundation (www.soundation.com) will look familiar to anyone who has used Garageband on a Mac. It allows you to upload, record or use virtual instruments to create up to four recorded tracks and mix them online using the site. You can add effects, change the balance, everything you’d expect in a full piece of software. You can then save and share the results.