HTML files are typically much smaller than FrameMaker chapter files. A large HTML file can take an unacceptable amount of time to download from the Web. If you are producing HTML, XML, or HTML-based Help, you will want to split up your FrameMaker files so each topic is in its own file.
If you are converting your FrameMaker index to HTML, or using Mif2Go to generate an index for HTML-based Help, Mif2Go automatically creates an index entry for each split file when a split occurs within text between index-marker <$startrange> and <$endrange> entries.
> 17 Splitting and extracting files > 17.2 Splitting files