markdown-prepare.el (Source)

(autoload 'markdown-mode
"markdown-mode"
"Major mode for editing markdown files." t)
(add-to-list 'auto-mode-alist '("\\.md\\'" . markdown-mode))
(add-to-list 'auto-mode-alist '("\\.kd\\'" . markdown-mode))
(add-hook 'markdown-mode-hook 'turn-on-auto-fill)