osCommerce (“Open Source Commerce”) is an e-commerce and online store-management software program. It can be used on any web server that has PHP and MySQL installed. Being one of the most veteran packages of its kind, osCommerce has spawned a number of forks including Zen Cart.
osCommerce is a self-hosted, and there are no limits to the number of products that can be uploaded to the system.
One of the strongest points of osCommerce is that after so many years being actively developed, the software can today be complemented with thousands of free community add-ons that cater for just about any in-store functionality imaginable. Most add-ons are developed by an active community that also creates many 3rd party services that integrate easily with the system and that can be downloaded for free.
osCommerce can support just about any existing payment processors, including BitCoin, Authorizenet, SagePay and PayPal. The software also supports many processor integrations, such as Dwolla and Checkout by Amazon.