The document defines several terms related to online travel booking and digital marketing: OTA refers to online travel agencies like Expedia that allow booking travel through the internet. Last minute booking apps allow booking hotel rooms very close to the travel date through mobile apps. Direct booking involves booking directly through a hotel or travel company website. SEM involves promoting websites through search engine optimization and advertising to increase search engine rankings. Customer engagement refers to customer interactions with companies through online and offline media. SEO optimizes websites to rank higher in organic search results. Paid search involves paid listing placements in search engines on a cost-per-click basis. Interactive advertising uses online and offline media to promote products through two-way engagement between consumers and companies