Substack is a publishing platform that combines newsletter creation, distribution, and monetization in a single service. Founded in 2017, Substack has grown rapidly by offering writers and content creators a straightforward way to reach their audience directly and earn subscription revenue.

The platform provides simple yet effective tools for writing, editing, and sending email newsletters, along with integrated website publishing. Substack's core innovation is its built-in paid subscription model, allowing writers to monetize their content directly from readers without needing to implement separate payment systems or subscription management.

Substack handles all technical aspects including email delivery, subscriber management, payment processing, and content hosting. The platform offers analytics on readership, open rates, subscription growth, and revenue. While it lacks the advanced segmentation and automation features of traditional ESPs, Substack compensates with its focus on simplicity and direct monetization.

The service has gained significant popularity among journalists, authors, analysts, and subject matter experts looking to build independent media businesses. Substack's writer-centric approach, combined with its emphasis on direct reader relationships and sustainable business models, has positioned it as a compelling alternative to both traditional publishing and social media platforms.