Short Code are primarily used for lead generation or receiving feedbacks from the customers or for providing information/updates to the customers.
Every company which wants to avail this service will be provided with a Keyword. Keyword is a unique identifier for your company.
Every message which starts with that keyword will be forwarded to your panel. Also the client can configure if auto-reply sms needs to be sent to their customers.
Long numbers enable businesses to have their own number, rather than short codes which are generally shared across a lot of brands.