Mosaic was the first 'free' cross-platform World Wide Web browser. This was significant as it made the Internet accessible to the people. Mosaic was one of the first browsers to render images inline to the HTML.
Versions can be found here.
Compiled versions can be found here. It is somewhat common to have to compile Mosiac on the host platform... It does require motif which can be difficult on 'modern' systems. There is a port to newer Linux systems here.