for a merchant\\\'s company obtains a PayPal-issued API certificate file and makes API calls
 for the company from the company\\\'s own web server. Third-Party Model Another person or 
company makes API calls on the merchant\\\'s behalf. The merchant grants the third-party his
 permission to make API calls for him. Examples A web hosting service has its own API certificate,
 API username, and API password. Its customers, who are merchants that use PayPal, give the hosting
 service their permission to make API calls on their behalf. The hosting service includes a merchant\\\'s email address 
on file with PayPal in the \\\"Subject\\\" field of an API call. A merchant company\\\'s programmer has her own PayPal-issued 
API signature, username, and password. She gives permission to a shopping cart ser