Twitter's internal design team built Bootstrap to solve a specific problem: every internal tool at Twitter looked different. Different teams had different CSS conventions, different button styles, different form designs. Onboarding a new engineer meant learning the CSS quirks of whatever tool they joined.
Mark Otto and Jacob Thornton open-sourced it on GitHub in August 2011. By January 2012 it was the most-starred project on GitHub. By 2013 it was estimated to be running on 1-2% of all websites - and 10-15% of sites built with a CSS framework.
We adopted Bootstrap 1.x in late 2011 for internal tools. By mid-2012 we were using it as the default starting point for client projects. By 2013, almost every project we started was Bootstrap-based.
What Bootstrap Actually Provided
Bootstrap 2.x (released January 2012, the version that drove mass adoption) consisted of:
1. A 12-column grid system
<!-- Bootstrap's grid - the core innovation -->
<div class="container">
<div class="row">
<!-- 4 columns wide -->
<div class="span4">
Sidebar content
</div>
<!-- 8 columns wide -->
<div class="span8">
Main content
</div>
</div>
<div class="row">
<!-- Three equal columns -->
<div class="span4">Column 1</div>
<div class="span4">Column 2</div>
<div class="span4">Column 3</div>
</div>
</div>
Before Bootstrap, every project had its own grid implementation. Some used 960.gs (a popular 960px grid system). Some used Blueprint CSS. Most had hand-crafted float: left columns with manually calculated widths and clear: both hacks. Bootstrap's grid wasn't technically superior to these - it was just consistently documented and available.
2. Styled UI components
<!-- Buttons - consistent across all projects -->
<button class="btn">Default</button>
<button class="btn btn-primary">Primary</button>
<button class="btn btn-danger">Delete</button>
<button class="btn btn-success">Save</button>
<!-- Alert boxes -->
<div class="alert alert-success">
<button type="button" class="close" data-dismiss="alert">×</button>
Successfully saved!
</div>
<div class="alert alert-error">
An error occurred. Please try again.
</div>
<!-- Navigation bar -->
<div class="navbar navbar-fixed-top">
<div class="navbar-inner">
<div class="container">
<a class="brand" href="/">Aunimeda</a>
<ul class="nav">
<li class="active"><a href="/">Home</a></li>
<li><a href="/about">About</a></li>
<li><a href="/contact">Contact</a></li>
</ul>
</div>
</div>
</div>
3. Form styling
<!-- Bootstrap 2.x form - horizontal layout -->
<form class="form-horizontal">
<div class="control-group">
<label class="control-label" for="email">Email</label>
<div class="controls">
<input type="email" id="email" placeholder="you@example.com">
<span class="help-inline">We'll never share your email.</span>
</div>
</div>
<div class="control-group error">
<label class="control-label" for="username">Username</label>
<div class="controls">
<input type="text" id="username" value="taken_name">
<span class="help-inline">Username already taken.</span>
</div>
</div>
<div class="form-actions">
<button type="submit" class="btn btn-primary">Save</button>
<button type="reset" class="btn">Cancel</button>
</div>
</form>
Bootstrap 2's Responsive Grid (Added in 2.0.1)
Bootstrap 2 added responsive breakpoints. This was a significant addition - a grid system that collapsed columns on small screens:
<!-- Responsive row - columns stack on mobile -->
<div class="row-fluid">
<div class="span8">
<!-- Takes 8/12 on desktop, full width on mobile -->
Main content
</div>
<div class="span4">
<!-- Takes 4/12 on desktop, full width on mobile -->
Sidebar
</div>
</div>
/* Bootstrap's responsive CSS - included as a separate file in 2.x */
@media (max-width: 767px) {
.row-fluid [class*="span"] {
display: block;
float: none;
width: 100%;
margin-left: 0;
}
}
The row-fluid vs row distinction was an oddity of Bootstrap 2 that Bootstrap 3 cleaned up by making all grids fluid by default.
What We Built on Bootstrap 2.x
Our first Bootstrap admin dashboard (December 2011):
<!DOCTYPE html>
<html lang="en">
<head>
<link rel="stylesheet" href="/bootstrap/css/bootstrap.min.css">
<link rel="stylesheet" href="/bootstrap/css/bootstrap-responsive.min.css">
</head>
<body>
<div class="navbar navbar-fixed-top">
<div class="navbar-inner">
<a class="brand" href="/">Dashboard</a>
<ul class="nav pull-right">
<li><a href="/logout">Logout</a></li>
</ul>
</div>
</div>
<div class="container" style="margin-top: 60px;">
<!-- Stats row -->
<div class="row">
<div class="span3">
<div class="well">
<h2>1,247</h2>
<p class="muted">Total Orders</p>
</div>
</div>
<div class="span3">
<div class="well">
<h2>$48,320</h2>
<p class="muted">Revenue</p>
</div>
</div>
<div class="span3">
<div class="well">
<h2>342</h2>
<p class="muted">Active Users</p>
</div>
</div>
<div class="span3">
<div class="well">
<h2>18</h2>
<p class="muted">Pending</p>
</div>
</div>
</div>
<!-- Data table -->
<table class="table table-striped table-bordered table-hover">
<thead>
<tr>
<th>#</th>
<th>Customer</th>
<th>Amount</th>
<th>Status</th>
<th>Actions</th>
</tr>
</thead>
<tbody>
<tr>
<td>1024</td>
<td>John Doe</td>
<td>$129.00</td>
<td><span class="label label-success">Shipped</span></td>
<td>
<a href="#" class="btn btn-mini">View</a>
<a href="#" class="btn btn-mini btn-danger">Cancel</a>
</td>
</tr>
</tbody>
</table>
</div>
<script src="/bootstrap/js/bootstrap.min.js"></script>
</body>
</html>
This admin panel took 45 minutes to build a functional first version. Before Bootstrap, the equivalent styling took 3-4 hours. The business value was real: faster iteration, consistent UI, lower QA surface area.
The Downside: The Bootstrap Web
By 2013 there was a recognizable "Bootstrap aesthetic." The default blue primary button, the gray nav, the specific border radius, the well container. Every startup's MVP looked the same.
More seriously, developers stopped thinking about CSS. Bootstrap was so comprehensive that you could build entire projects without writing a meaningful CSS rule. When Bootstrap's defaults didn't quite work, developers added !important hacks:
/* The shame file - every Bootstrap project had one */
.btn-primary {
background-color: #ff6600 !important; /* Override Bootstrap's blue */
border-color: #cc5200 !important;
}
.navbar {
height: 80px !important; /* Client wants taller nav */
}
/* And then the cascade of fixes caused by the above */
.navbar .navbar-brand {
line-height: 80px !important;
}
The !important proliferation was a symptom of the same underlying problem: Bootstrap's CSS specificity was high, and overriding it without understanding CSS specificity produced increasingly hacky results.
The solution - and Bootstrap 3 acknowledged this - was to use Bootstrap's LESS/SASS variables to customize at the source, not override at the surface:
// _variables.scss - customize Bootstrap before compilation
$brand-primary: #ff6600;
$navbar-height: 80px;
$btn-border-radius-base: 4px;
$font-size-base: 15px;
// Then import Bootstrap with your variables
@import "bootstrap";
Bootstrap's Actual Legacy
Bootstrap 3 (2013), Bootstrap 4 (2018), Bootstrap 5 (2021) - the framework is still maintained and still used. But its cultural legacy is more significant than its code.
It proved that shared component libraries were better than each project inventing its own. It created the expectation that CSS frameworks should be responsive by default. It established the 12-column grid as the mental model for web layout that most developers still use. It popularized modifier classes (.btn.btn-primary, .alert.alert-success) as a CSS architecture pattern.
The post-Bootstrap world has Material Design, Tailwind CSS, component libraries from every major framework. All of them are responses to Bootstrap - either building on its patterns or explicitly rejecting them.
The uniform look of the early 2010s web was the price of dramatically lower development friction. For projects where differentiated design mattered, that was a real cost. For internal tools, MVPs, and clients who needed working software faster than beautiful software, Bootstrap was exactly right.
Aunimeda builds modern web frontends - from single-page applications to complex multi-locale sites.
Contact us to discuss your frontend project. See also: Web Development, Corporate Website Development