Bulk SMS service is a mass messaging system that allows businesses and organizations to send text messages to large groups of people at once. The messages are sent via an SMS gateway to a database of phone numbers, enabling businesses to reach their audience quickly and effectively. The main advantage of bulk SMS is its high open rate, which is often over 98%. This makes it an effective and cost-efficient marketing tool for promoting products, services, and events, as well as for keeping customers informed and engaged.