In addition to Jagan's blog ,i want to add some more information to this.
S60 is software in S60 phones that makes them more like small computers than conventional mobile phones. S60 handles basic phone functionality as well as advanced applications. Web Browser for S60 is based on the WebCore and JavaScriptCore open source components that are used by Apple's Safari Internet browser. These components are based on KDE's Konqueror open source project.
Web Browser for S60 has numerous benefits:
1) Superior user experience
2) Extensibility
3) Differentiation
4) Interoperability