#menu {
float: left;
width: 25%;
background-color: #ff99CC;
overflow: auto;
}

html {
padding:0px;
margin:0px;
}
body {
background-color: #e1ddd9;
font-size: 12px;
font-family: Verdana, Arial, SunSans-Regular, Sans-Serif;
color:#564b47;
padding:0px 20px;
margin:0px;
}
#content {
float: left;
width: 75%;
background-color: #fff;
margin:0px 0px 50px 0px;
overflow: auto;
}

Figure 8-21. Examples of negative vertical margins

You'll notice the "pulling" effect of negative top and bottom margins. This is really no different from the way in which negative horizontal margins cause an element to push outside of its parent. Consider:

Another example is web enabling legacy systems. It is very feasible to create a Java web ennoblement application server that simply uses the services provided by the underlying legacy system. Instead of rewriting the legacy system, if the system can be made to communicate results and parameters through XML, the new and old system can work together without throwing away a company's investment in the legacy system.

By making the W3C the keeper of the XML standard, it ensures that no one vendor should be able to cause interoperability problems to occur between systems that use the open standard. This should be reassuring to most companies making an investment in this technology, by being vendor neutral, this solution proposes to keep even small companies out of reach of big companies choosing to change the standards on them. For example, if a big company chooses to change the platform at its whim, then most other companies relying on that platform suffer. By keeping all data in XML and using XML in communications protocols, companies can maximize the lifetime of their investment in their products and solutions.