OBD - Office Binder Document is a file extension that was made for linking Microsoft document files together. It was created by Office Binder. You will also be able to use this extension to store files. They all include a wide range of office document objects. It can also be used for linking the contents of the files together right from Word, Excel, and many others. You will simply be able to go online if you would like to download and take advantage of this file extension. It is also included with Microsoft Office 95,97, and even 2000 but not in any of the newer versions.