w3schools example for overflow:hidden [duplicate] - css

Question

This question already has answers here:
CSS overflow:hidden with floats
(5 answers)
Closed 6 years ago.
I already know about overflow:hidden that It hide text when text can't be filled in border. but I don't know why the following coding need it.
This code creates navigation bar but if I erase overflow:hidden, It doesn't work. I want to know about this happening. hidden works for what?
please help.
ul {
list-style-type: none;
margin: 0;
padding: 0;
overflow: hidden;
background-color: #333;
}
li {
float: left;
}
li a {
display: block;
color: white;
text-align: center;
padding: 14px 16px;
text-decoration: none;
}
li a:hover {
background-color: #111;
}
<ul>
<li><a class="active" href="#home">Home</a></li>
<li>News</li>
<li>Contact</li>
<li>About</li>
</ul>

Answer 1

That is because you are not clearing float left.Please remove overflow:hidden; from code and add
ul:after{
Content:"";
display:block;
clear:both;
}
This will work properly.

Answer 2

its about float left when child has this property then parent leave child's height property so then ul tag invisible becouse that have no height
so us like this
ul {
list-style-type: none;
margin: 0;
padding: 0;
background-color: #333;
}
li {
display: inline-block;
}
li a {
display: block;
color: white;
text-align: center;
padding: 14px 16px;
text-decoration: none;
}
li a:hover {
background-color: #111;
}
<ul>
<li><a class="active" href="#home">Home</a></li>
<li>News</li>
<li>Contact</li>
<li>About</li>
</ul>
Hope this helps you
THANKS

Answer 3

Actually it works well if you give ul a height.
Here the overflow is well explained: W3C
ul {
list-style-type: none;
margin: 0;
padding: 0;
background-color: #333;
height:46px;
}
li {
float: left;
}
li a {
display: block;
color: white;
text-align: center;
padding: 14px 16px;
text-decoration: none;
}
li a:hover {
background-color: #111;
}
<ul>
<li><a class="active" href="#home">Home</a></li>
<li>News</li>
<li>Contact</li>
<li>About</li>
</ul>