HTML5 Boilerplate homepage | Documentation table of contents

The HTML

By default, HTML5 Boilerplate provides two html pages:

index.html – a default HTML skeleton that should form the
basis of all pages on your website
404.html – a placeholder 404 error page

`index.html`

The `no-js` Class

The no-js class is provided in order to allow you to more easily and
explicitly add custom styles based on whether JavaScript is disabled
(.no-js) or enabled (.js). Using this technique also helps avoid the FOUC.

Language Attribute

Please consider specifying the language of your content by adding a value to the lang
attribute in the <html> as in this example:

<html class="no-js" lang="en">

The order of the `<title>` and `<meta>` tags

The order in which the <title> and the <meta> tags are specified is
important because:

1) the charset declaration (<meta charset="utf-8">):

must be included completely within the first 1024 bytes of the document
should be specified as early as possible (before any content that could
be controlled by an attacker, such as a <title> element) in order to
avoid a potential encoding-related security issue in
Internet Explorer

2) the meta tag for compatibility mode
(<meta http-equiv="x-ua-compatible" content="ie=edge">):

needs to be included before all other tags except for the <title> and the other <meta> tags

`x-ua-compatible`

Internet Explorer 8/9/10 support document compatibility modes that affect the
way webpages are interpreted and displayed. Because of this, even if your site’s
visitor is using, let’s say, Internet Explorer 9, it’s possible that IE will not
use the latest rendering engine, and instead, decide to render your page using
the Internet Explorer 5.5 rendering engine.

Specifying the x-ua-compatible meta tag:

<meta http-equiv="x-ua-compatible" content="ie=edge">

or sending the page with the following HTTP response header

X-UA-Compatible: IE=edge

will force Internet Explorer 8/9/10 to render the webpage in the highest
available mode in the various cases when it may not, and therefore, ensure that anyone
browsing your site is treated to the best possible user experience that
browser can offer.

If possible, we recommend that you remove the meta tag and send only the
HTTP response header as the meta tag will not always work if your site is
served on a non-standard port, as Internet Explorer’s preference option
Display intranet sites in Compatibility View is checked by default.

If you are using Apache as your webserver, including the
.htaccess file takes care of
the HTTP header. If you are using a different server, check out our other server config.

Starting with Internet Explorer 11, document modes are deprecated.
If your business still relies on older web apps and services that were
designed for older versions of Internet Explorer, you might want to consider
enabling Enterprise Mode throughout your company.

Meta Description

The description meta tag provides a short description of the page.
In some situations this description is used as a part of the snippet
shown in the search results.

<meta name="description" content="This is a description">

Mobile Viewport

There are a few different options that you can use with the viewport meta tag. You can find out more in the Apple developer docs.
HTML5 Boilerplate comes with a simple setup that strikes a good balance for general use cases.

<meta name="viewport" content="width=device-width, initial-scale=1">

Web App Manifest

HTML5 Boilerplate includes a simple web app manifest file.

The web app manifest is a simple JSON file that allows you to control how your
app appears on a device’s home screen, what it looks like when it launches
in that context and what happens when it is launched. This allows for much greater
control over the UI of a saved site or web app on a mobile device.

It’s linked to from the HTML as follows:

        <link rel="manifest" href="site.webmanifest">

Our site.webmanifest contains a very skeletal “app” definition, just to show the basic usage.
You should fill this file out with more information about your site or application

Favicons and Touch Icon

The shortcut icons should be put in the root directory of your site. favicon.ico
is automatically picked up by browsers if it’s placed in the root. HTML5
Boilerplate comes with a default set of icons (include favicon and one Apple
Touch Icon) that you can use as a baseline to create your own.

Please refer to the more detailed description in the Extend section
of these docs.

The Content Area

The central part of the boilerplate template is pretty much empty. This is
intentional, in order to make the boilerplate suitable for both web page and
web app development.

Browser Upgrade Prompt

The main content area of the boilerplate includes a prompt to install an up to
date browser for users of IE 8 and lower. If you intended to support IE 8, then you
should remove the snippet of code.

Modernizr

HTML5 Boilerplate uses a custom build of Modernizr.

Modernizr is a JavaScript library which adds classes to
the html element based on the results of feature test and which ensures that
all browsers can make use of HTML5 elements (as it includes the HTML5 Shiv).
This allows you to target parts of your CSS and JavaScript based on the
features supported by a browser.

Starting with version 3 Modernizr can be customized using the modernizr-config.json and the
Modernizr command line utility.

What About Polyfills?

If you need to include polyfills
in your project, you must make sure those load before any other JavaScript. If you’re
using some polyfill CDN service, like cdn.polyfill.io,
just put it before the other scripts in the bottom of the page:

    <script src="js/vendor/modernizr-3.6.0.min.js"></script>
    <script src="https://cdn.polyfill.io/v2/polyfill.min.js"></script>
    <script src="https://code.jquery.com/jquery-3.3.1.min.js" integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8=" crossorigin="anonymous"></script>
    <script>window.jQuery || document.write('<script src="js/vendor/jquery-3.3.1.min.js"><\/script>')</script>
    <script src="js/plugins.js"></script>
    <script src="js/main.js"></script>
</body>

If you like to just include the polyfills yourself, you could include them in
js/plugins.js. When you have a bunch of polyfills to load in, you could
also create a polyfills.js file in the js/vendor directory or include the files
individually and combine them using a build tool. Always ensure that the polyfills
are all loaded before any other JavaScript.

There are some misconceptions about Modernizr and polyfills. It’s important
to understand that Modernizr just handles feature checking, not polyfilling
itself. The only thing Modernizr does regarding polyfills is that the team
maintains a huge list of cross Browser polyfills.

jQuery CDN for jQuery

The jQuery CDN version of the jQuery JavaScript library is referenced towards
the bottom of the page. A local fallback of jQuery is included for rare instances
when the CDN version might not be available, and to facilitate offline
development.

The jQuery CDN version was chosen over other potential candidates
(like Google’s Hosted Libraries)
because it’s fast (comparable or faster than Google by some measures)
and, (unlike Google’s CDN) is available to China’s hundreds of millions of internet users.
For many years we chose
the Google Hosted version over the jQuery CDN because it was available
over HTTPS (the jQuery CDN was not,) and it offered a better chance of
hitting the cache lottery owing to the popularity of the Google CDN.
The first issue is no longer valid and the second is far outweighed by
being able to serve jQuery to Chinese users.

While the jQuery CDN is a strong default solution your site or application may
require a different configuration. Testing your site with services like
WebPageTest and browser tools like
PageSpeed Insights will help you examine the real
world performance of your site and can show where you can optimize your specific
site or application.

Google Universal Analytics Tracking Code

Finally, an optimized version of the Google Universal Analytics tracking code is
included. Google recommends that this script be placed at the top of the page.
Factors to consider: if you place this script at the top of the page, you’ll
be able to count users who don’t fully load the page, and you’ll incur the max
number of simultaneous connections of the browser.

Further information:

N.B. The Google Universal Analytics snippet is included by default mainly
because Google Analytics is currently one of the most popular tracking solutions out there.
However, its usage isn’t set in stone, and you SHOULD consider exploring the
alternatives
and use whatever suits your needs best!