Question

I started using Twitter Bootstrap and trying to place two forms side by side. By default if I place two forms on the page they follow one after another, what attribute should I apply to place these forms side by side with 50% width.

Answer 1

You can use the grid features of twitter bootstrap.
Something like:

<div class="row">
    <div class="span6">
        <form>[...]</form>
    </div>
    <div class="span6">
        <form>[...]</form>
    </div>
</div>

EDIT:

with Twitter Bootstrap 3.x

<div class="row">
    <div class="col-sm-6">
        <form>[...]</form>
    </div>
    <div class="col-sm-6">
        <form>[...]</form>
    </div>
</div>

nb: in col-sm-6, sm stands for small, it means this grid will apply only for devices with a viewport larger than 768px (with TWBS default settings)