Bootstrap : Nav Bar

<div class="container" ><!-- navbar container start -->
	 <nav class="navbar navbar-expand-lg navbar-light bg-light fixed-top" >
		  
		  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
				<span class="navbar-toggler-icon"></span>
		  </button>

		  <div class="collapse navbar-collapse" id="navbarSupportedContent">
			  <!-- "navbar-brand"may contain text or image equivalent to size of toggler -->
			  <a class="navbar-brand" href="#">Navbar</a><!-- if this is place just below <nav class="navbar , the toggler will be shown in right -->
				<ul class="navbar-nav mr-auto">
				  <li class="nav-item active">
					<a class="nav-link" href="#">Home <span class="sr-only">(current)</span></a>
				  </li>
				  <li class="nav-item">
					<a class="nav-link" href="#">Link</a>
				  </li>
				  <li class="nav-item dropdown">
					<a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
					  Dropdown
					</a>
					<div class="dropdown-menu" aria-labelledby="navbarDropdown">
					  <a class="dropdown-item" href="#">Action</a>
					  <a class="dropdown-item" href="#">Another action</a>
					  <div class="dropdown-divider"></div>
					  <a class="dropdown-item" href="#">Something else here</a>
					</div>
				  </li>
				  <li class="nav-item">
					<a class="nav-link disabled" href="#">Disabled</a>
				  </li>
				</ul>
				<form class="form-inline my-2 my-lg-0">
				  <input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
				  <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
				</form>
		  </div>
		</nav>
</div><!-- navbar container end -->