reveal.js comes with a broad range of features including [nested slides](https://github.com/hakimel/reveal.js#markup), [markdown contents](https://github.com/hakimel/reveal.js#markdown), [PDF export](https://github.com/hakimel/reveal.js#pdf-export), [speaker notes](https://github.com/hakimel/reveal.js#speaker-notes) and a [JavaScript API](https://github.com/hakimel/reveal.js#api). It's best viewed in a browser with support for CSS 3D transforms but [fallbacks](https://github.com/hakimel/reveal.js/wiki/Browser-Support) are available to make sure your presentation can still be viewed elsewhere.
Slides are written using HTML or markdown but there's also an online editor for those of you who prefer a more traditional user interface. Give it a try at [www.rvl.io](http://www.rvl.io).
Markup heirarchy needs to be ``<divclass="reveal"><divclass="slides"><section>`` where the ``<section>`` represents one slide and can be repeated indefinitely. If you place multiple ``<section>``'s inside of another ``<section>`` they will be shown as vertical slides. The first of the vertical slides is the "root" of the others (at the top), and it will be included in the horizontal sequence. For example:
It's possible to write your slides using Markdown. To enable Markdown, add the ```data-markdown``` attribute to your ```<section>``` elements and wrap the contents in a ```<scripttype="text/template">```liketheexamplebelow.
This is based on [data-markdown](https://gist.github.com/1343518) from [Paul Irish](https://github.com/paulirish) which in turn uses [showdown](https://github.com/coreyti/showdown/). This is sensitive to indentation (avoid mixing tabs and spaces) and line breaks (avoid consecutive breaks).
At the end of your page you need to initialize reveal by running the following code. Note that all config values are optional and will default as specified below.
Note that the new default vertical centering option will break compatibility with slides that were using transitions with backgrounds (`cube` and `page`). To restore the previous behavior, set `center` to `false`.
Reveal.js doesn't _rely_ on any third party scripts to work but a few optional libraries are included by default. These libraries are loaded as dependencies in the order they appear, for example:
If you set ``data-state="somestate"`` on a slide ``<section>``, "somestate" will be applied as a class on the document element when that slide is opened. This allows you to apply broad style changes to the page based on the active slide.
An 'slidechanged' event is fired each time the slide is changed (regardless of state). The event object holds the index values of the current slide as well as a reference to the previous and current slide HTML nodes.
Some libraries, like MathJax (see [#226](https://github.com/hakimel/reveal.js/issues/226#issuecomment-10261609)), get confused by the transforms and display states of slides. Often times, this can be fixed by calling their update or render function from this callback.
It's easy to link between slides. The first example below targets the index of another slide whereas the second targets a slide with an ID attribute (```<sectionid="some-slide">```):
You can also add relative navigation links, similar to the built in reveal.js controls, by appending one of the following classes on any element. Note that each element is automatically given an ```enabled``` class when it's a valid navigation route based on the current slide.
Just press »F« on your keyboard to show your presentation in fullscreen mode. Press the »ESC« key to exit fullscreen mode.
### Fragments
Fragments are used to highlight individual elements on a slide. Every elmement with the class ```fragment``` will be stepped through before moving on to the next slide. Here's an example: http://lab.hakim.se/reveal-js/#/16
The default fragment style is to start out invisible and fade in. This style can be changed by appending a different class to the fragment:
Multiple fragments can be applied to the same element sequentially by wrapping it, this will fade in the text on the first step and fade it back out on the second.
```
<section>
<spanclass="fragment fade-out">
<spanclass="fragment fade-out">I'll fade in, then out</span>
1. Open your presentation with [css/print/pdf.css](https://github.com/hakimel/reveal.js/blob/master/css/print/pdf.css) included on the page. The default index HTML lets you add *print-pdf* anywhere in the query to include the stylesheet, for example: [lab.hakim.se/reveal-js?print-pdf](http://lab.hakim.se/reveal-js?print-pdf).
reveal.js comes with a speaker notes plugin which can be used to present per-slide notes in a separate browser window. The notes window also gives you a preview of the next upcoming slide so it may be helpful even if you haven't written any notes. Append ```?notes``` to presentation URL or press the 's' key on your keyboard to open the notes window.
By default notes are written using standard HTML, see below, but you can add a ```data-markdown``` attribute to the ```<aside>``` to write them using Markdown.
Oh hey, these are some notes. They'll be hidden in your presentation, but you can see them if you open the speaker notes window (hit 's' on your keyboard).
In some cases it can be desirable to run notes on a separate device from the one you're presenting on. The Node.js-based notes plugin lets you do this using the same note definitions as its client side counterpart. Include the requried scripts by adding the following dependencies:
reveal.js is built using the task-based command line build tool [grunt.js](http://gruntjs.com) ([installation instructions](https://github.com/gruntjs/grunt#installing-grunt)). With Node.js and grunt.js installed, you need to start by running ```npm install``` in the reveal.js root. When the dependencies have been installed you should run ```grunt watch``` to start monitoring files for changes.
If you want to customise reveal.js without running grunt.js you can alter the HTML to point to the uncompressed source files (css/reveal.css & js/reveal.js).
