Reach is a simple yet powerful email and SMS marketing builder offered by SalesStream.ai that enables users to achieve expert-level marketing results without being experts themselves. The product enhances marketing efficiency and effectiveness by helping users create and automatically send personalized messages through features such as personalization, scalability, CRM integration, and spreadsheet integration. Background information on Reach indicates it is designed to help users expand their influence through meaningful connections, making it particularly suitable for business users who require personalized and automated marketing campaigns.