Serverless form handling on Netlify-hosted sites — detects HTML forms at deploy time, stores submissions, filters spam, and sends notifications. Use when adding a contact form, lead-capture form, file-upload form, or newsletter signup to a Netlify site; wiring AJAX form submission; setting up a custom thank-you page; adding a honeypot or reCAPTCHA to a form; getting forms working in Next.js, Nuxt, SvelteKit, Astro, or Gatsby; reading form submissions via the Netlify API; or debugging missing submissions and forms that silently fail to register.