Konqueror is KDE's Webbrowser and swiss-army-knife for any kind of
file-management and file previewing.

Features :
Webbrowsing using KHTML or KDEWebKit as rendering engines
File management using most of Dolphin's features (including version-control,
service menus and the basic UI)
File management on ftp and sftp servers
Full featured FTP-client (you can split views to display local and remote
folders and previews in the same window)
Embedded applications to preview and edit files (e.g. Okular and KOffice for
documents, Gwenview for pictures, KTextEditor for text-files)
Different kinds of plugins: Service-menus, KParts (embedded applications),
KIO (accessing files using special protocols like http or ftp) and
KPart-plugins (like AdBlocker...)