Zencart is an Open Source Online Store Management System.

• It is PHP-based & uses MySQL database &HTML components.
• It also provides support for different languages and currencies and is freely available under the GNU General Public License.
• Shopping Cart is set to recieve from major credit cards
• Several other payment gateways are also provided

Key features of Zen Cart are listed below:-

1. Multiple language support
2. Multiple customer modes
3. Unlimited category depth
4. Multiple sales and discounts
5. Multiple display modes
6. XHTML 1.0 compliant template system
7. Extra pages
8. Multiple ad banner controller
9. Multiple shipping options
10. Multiple payment options
11. Newsletter manager
12. Discount coupons
13. Gift certificates
14. Featured products
15. Quantity discounts
16. phpBB integration through external module
17. Checks the database server before installing.

 
Few drawbacks of zencart are as follows:

1. Although Zen Cart improved the shop management and administration with the template system, still it suffers from the fact that editing core files for customizing is often required(no real modular structure).
2. In case of heavy customizing, maintaining and updating of software seems to be a tedious job.