Hypothesis is a free web and PDF annotation tool that allows users to collaboratively annotate, highlight, and tag web pages and PDF documents. With Hypothesis, users can hold discussions, read socially, organize their research, and take personal notes on webpages, PDFs, and EPUBs.

The platform provides a seamless and intuitive user experience, making it easy for users to annotate and highlight important information on web pages and PDF documents. The annotation tools are comprehensive, allowing users to add text, highlight text, and draw shapes to emphasize specific points.

One of the standout features of Hypothesis is its collaborative functionality. Users can invite others to join their annotations, enabling real-time discussions and collaboration on documents. This makes it a great tool for teams working on research projects or for educators and students to engage in interactive learning.

Overall, Hypothesis is a powerful and versatile tool for web and PDF annotation. Its user-friendly interface and collaborative features make it an excellent choice for individuals and teams looking to enhance their research and reading experience.