Sidebar menus are used in every page. They are very common in admin panels. The following code is an example of such a menus. It uses icons as the always showing part of the menu. When the user hovers it, the full menu appears with the texts. Very useful!

HTML
<!-- this script got from www.devanswer.com -->
<div class="area"></div><nav class="main-menu"> <ul> <li> <a href="http://devanswer.com"> <i class="fa fa-home fa-2x"></i> <span class="nav-text"> Dashboard </span> </a> </li> <li class="has-subnav"> <a href="#"> <i class="fa fa-laptop fa-2x"></i> <span class="nav-text"> Stars Components </span> </a> </li> <li class="has-subnav"> <a href="#"> <i class="fa fa-list fa-2x"></i> <span class="nav-text"> Forms </span> </a> </li> <li class="has-subnav"> <a href="#"> <i class="fa fa-folder-open fa-2x"></i> <span class="nav-text"> Pages </span> </a> </li> <li> <a href="#"> <i class="fa fa-bar-chart-o fa-2x"></i> <span class="nav-text"> Graphs and Statistics </span> </a> </li> <li> <a href="#"> <i class="fa fa-font fa-2x"></i> <span class="nav-text"> Quotes </span> </a> </li> <li> <a href="#"> <i class="fa fa-table fa-2x"></i> <span class="nav-text"> Tables </span> </a> </li> <li> <a href="#"> <i class="fa fa-map-marker fa-2x"></i> <span class="nav-text"> Maps </span> </a> </li> <li> <a href="#"> <i class="fa fa-info fa-2x"></i> <span class="nav-text"> Documentation </span> </a> </li> </ul> <ul class="logout"> <li> <a href="#"> <i class="fa fa-power-off fa-2x"></i> <span class="nav-text"> Logout </span> </a> </li> </ul> </nav><a style="font-size: 8pt; text-decoration: none" target="_blank" href="http://www.devanswer.com">Developer Code</a>
CSS
@import url(https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css);
}
@import url(https://fonts.googleapis.com/css?family=Titillium+Web:300);


.fa-2x {
font-size: 2em;
}
.fa {
position: relative;
display: table-cell;
width: 60px;
height: 36px;
text-align: center;
vertical-align: middle;
font-size:20px;
}


.main-menu:hover,nav.main-menu.expanded {
width:250px;
overflow:visible;
}

.main-menu {
background:#212121;
border-right:1px solid #e5e5e5;
position:absolute;
top:0;
bottom:0;
height:100%;
left:0;
width:60px;
overflow:hidden;
-webkit-transition:width .05s linear;
transition:width .05s linear;
-webkit-transform:translateZ(0) scale(1,1);
z-index:1000;
}

.main-menu>ul {
margin:7px 0;
}

.main-menu li {
position:relative;
display:block;
width:250px;
}

.main-menu li>a {
position:relative;
display:table;
border-collapse:collapse;
border-spacing:0;
color:#999;
 font-family: arial;
font-size: 14px;
text-decoration:none;
-webkit-transform:translateZ(0) scale(1,1);
-webkit-transition:all .1s linear;
transition:all .1s linear;
  
}

.main-menu .nav-icon {
position:relative;
display:table-cell;
width:60px;
height:36px;
text-align:center;
vertical-align:middle;
font-size:18px;
}

.main-menu .nav-text {
position:relative;
display:table-cell;
vertical-align:middle;
width:190px;
  font-family: 'Titillium Web', sans-serif;
}

.main-menu>ul.logout {
position:absolute;
left:0;
bottom:0;
}

.no-touch .scrollable.hover {
overflow-y:hidden;
}

.no-touch .scrollable.hover:hover {
overflow-y:auto;
overflow:visible;
}

a:hover,a:focus {
text-decoration:none;
}

nav {
-webkit-user-select:none;
-moz-user-select:none;
-ms-user-select:none;
-o-user-select:none;
user-select:none;
}

nav ul,nav li {
outline:0;
margin:0;
padding:0;
}
.main-menu li:hover>a,nav.main-menu li.active>a,.dropdown-menu>li>a:hover,.dropdown-menu>li>a:focus,.dropdown-menu>.active>a,.dropdown-menu>.active>a:hover,.dropdown-menu>.active>a:focus,.no-touch .dashboard-page nav.dashboard-menu ul li:hover a,.dashboard-page nav.dashboard-menu ul li.active a {
color:#fff;
background-color:#5fa2db;
}
.area {
float: left;
background: #e2e2e2;
width: 100%;
height: 100%;
}
@font-face {
  font-family: 'Titillium Web';
  font-style: normal;
  font-weight: 300;
  src: local('Titillium WebLight'), local('TitilliumWeb-Light'), url(http://devanswer.com/codes/files/sidefont.woff) format('woff');
}