This is a list of file types which are automatically recognized by Extensions Manager as an extension to your system. Double click on this list to add or remove an item. This is a list of file types which should have an INIT resource to be recognized by Extensions Manager as an extension to your system. Double click on this list to add or remove an item. An INIT resource consists of a program which is executed by your Macintosh while starting up. Once executed the INIT resource adds functionality to your computer but it takes some memory space aside for its own use. This button dismisses this dialog after saving all of the changes you have made in the Configuration dialog. This button dismisses this dialog without saving any of the changes you have made in the Configuration dialog.