A: Yes there is. To put it in its most simple terms, aluminum fence basically is designed to
keep people out. Aluminum railings, on the other hand, are designed to keep people in. For example, balcony or deck railings are used to keep people safely in, while swimming pool fence is designed to keep kids out of the pool. Generally speaking, railings must meet IBC or IRC codes which specify this
fundamental requirement: able to withstand 200 or more pounds of lateral force. Fences, on the other hand, typically do not have to meet any codes with the exception of swimming pool fences. (Click swimming pool safety codes for more information on pool codes.) Therefore, a fence will not usually qualify or meet code where railing IS required as it is not designed to withstand the 200 pound limit.
Because railing usually needs to be much stronger than fence, it uses more and heavier aluminum, and therefore costs significantly more. This information courtesy of : http://www.aluminumfencespecialists.com/fence-and-railing.htm