A General Sales Agent (GSA) is an agent appointed by an airline to represent the airline and sell its products and services to customers within a certain territory or region. A GSA will handle the sales, marketing and customer service for the airline, and may also be responsible for other functions such as ticketing, airport operations, and cargo.

On the other hand, a Cargo Sales Agent (CSA) is a specific type of GSA that focuses solely on the cargo market. A CSA is responsible for selling cargo space on behalf of an airline or multiple airlines, and may also handle cargo operations, logistics, and freight forwarding services. In contrast to the GSA who is responsible for all aspects of an airlines operation a CSA's main focus is to sell the cargo space and handle all the logistics of the cargo market.

Both GSA and CSA are appointed by airlines and work as their representatives to handle sales, marketing, and customer service for the airline. However, while a GSA covers all aspects of the airline's operation, a CSA focuses specifically on the cargo market, selling cargo space and handling cargo logistics for the airline.

In summary, The main difference between GSA and CSA is that GSA is a general sales agent for an airline and is responsible for all aspects of airline operation in a certain territory or region, whereas CSA is a specific sales agent for cargo, responsible for selling cargo space and handling cargo logistics and operations for the airline or multiple airlines.