What is the difference between Packing and Packaging??

Packing is only the outward wraping of something.
Packaging is as a whole from concepting, marketing, promoting, designing the brand, label etc.. Packing is one of steps involved in packaging a product.

Packing: 包裝物 (hardware)
http://hk.dictionary.yahoo.com/search.html?q=1&s=packing&Submit=+%ACd%A6r+

Packaging: 外表的包裝(eg. 風格,方法) (software)
http://hk.dictionary.yahoo.com/search.html?q=1&s=packaging&Submit=+%ACd%A6r+

如: 糖紙就是packing, 糖紙設計等就是packaging.