overflow

значения свойства:

visible
hidden
scroll
auto
inherit

css/style.css

.a {
width: 230px;
height: 150px;
background-color: #3BA9DE;
overflow: hidden;
}
#div1 {
width: 230px;
height: 150px;
background-color: #56A31D;
}
.b {
width: 230px;
height: 150px;
background-color: #852E76;
}
.c {
width: 230px;
height: 150px;
background-color: #852E76;
overflow: visible;
}
div {
float: left;
display: inline;
}
.empty {
width: 20px;
height: 150px;
}

.a {
 width: 230px;
 height: 150px;
 background-color: #3BA9DE;
 overflow: hidden;
}

#div1 {
 width: 230px;
 height: 150px;
 background-color: #56A31D;
}

.b {
 width: 230px;
 height: 150px;
 background-color: #852E76;
}

.c {
 width: 230px;
 height: 150px;
 background-color: #852E76;
 overflow: visible;
}

div {
 float: left;
 display: inline;
}

.empty {
 width: 20px;
 height: 150px;
}

index.html

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>New Page</title>
<link href="css/style.css" rel="stylesheet" />
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
</head>
<body>
<div class="a">
But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii. But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii.
</div>
<div class="empty"></div>
<div id="div1">
But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii. But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii.
</div>
<div class="empty"></div>
<div class="b">
But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii. But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii.
</div>
<div class="empty"></div>
<div class="c">
But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii. But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii.
</div>
<script>
/*JavaScript*/
document.getElementById("div1").style.overflow = "scroll";
/*jQuery*/
$(document).ready(function () {
$(".b").css({ "overflow": "auto" });
});
</script>
</body>
</html>

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>New Page</title>
<link href="css/style.css" rel="stylesheet" />
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
</head>
<body>
<div class="a">
But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii. But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii.
</div>
<div class="empty"></div>
<div id="div1">
But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii. But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii.
</div>
<div class="empty"></div>
<div class="b">
But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii. But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii.
</div>
<div class="empty"></div>
<div class="c">
But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii. But it was a dream. Three weeks ago, I had been lying on a beach
in Hawaii. But I was not in Hawaii now. I was dreaming in my office
in Los Angeles. I had returned from my holiday and there was no
work for me. Nobody wanted to hire me. I went to my office every
day, but the telephone didn't ring. So I slept in my chair and I dreamt
about Hawaii.
</div>
<script>
/*JavaScript*/
document.getElementById("div1").style.overflow = "scroll";
/*jQuery*/
$(document).ready(function () {
$(".b").css({ "overflow": "auto" });
});
</script>
</body>
</html>