Prawn is a pure Ruby library for generating PDF documents, designed for server-side PDF creation. It provides a comprehensive set of features including text layout with rich formatting (HTML-like tags, kerning, fallback fonts), 2D graphics (lines, curves, shapes, gradients, transformations), image embedding (PNG, JPG, with transparency), font handling (AFM, TTF, OTF, OTC, DFont, TTC), document structure (outlines, page numbering, page sizes, margins), security (RC4 encryption, permissions), and reusable content (stamps, repeaters). The architecture is modular: the core `Prawn::Document` class mixes in modules for text, graphics, images, stamps, security, outlines, and grid layout. Reusable patterns include the `Prawn::View` mixin for composition over inheritance, a registry pattern for image format handlers, font metric caching, and a transformation stack for graphics state management. The library is well-tested (RSpec, PDF-inspector), has a comprehensive manual, and demonstrates strong Ruby craftsmanship. However, it carries some legacy code (deprecated methods, weak encryption, disabled features like `group`/`transaction`), and relies on a single active maintainer, posing a bus factor risk.