This is the idea behind jekyll: you write a text with any supported markup languages and pass it to jekyll and Jekyll transform it to HTML with going through a series of layout files.

here is a basic structure of jekyll directory:

.
├── _config.yml
├── _drafts
|   ├── begin-with-the-crazy-ideas.textile
|   └── on-simplicity-in-technology.markdown
├── _includes
|   ├── footer.html
|   └── header.html
├── _layouts
|   ├── default.html
|   └── post.html
├── _posts
|   ├── 2007-10-29-why-every-programmer-should-play-nethack.textile
|   └── 2009-04-26-barcamp-boston-4-roundup.textile
├── _data
|   └── members.yml
├── _site
└── index.html