Qwik is a resumable JavaScript framework that optimizes performance by rendering server-side HTML, allowing for progressive loading of code without a big bundle upfront. It uses an Optimizer written in Rust to transform the code at build time and leverages Vite for Hot Module Replacement (HMR) and bundling code. Qwik can be deployed on Netlify using either the Netlify CLI or manual git deployment methods, with the former providing a more streamlined experience. The process involves creating a new Qwik app using the CLI tool, installing dependencies, running the dev server locally, and then deploying the site to Netlify, where it can be configured for production deployment.