本文介紹一個由美國太空總署 （ NASA ）所制定的資料著錄格式--目錄交換格式 （ DIF ），地理資料由於無法直接檢索其內容， 故必須經由適當的著錄，來揭示其內容， 以利資料的整理、交換、檢索，DIF 便是由 NASA 所發展出來的一個資料著錄工具， NASA 因為擁有大量的地理方面衛星照片和遙測資料， 因此 DIF 也成為全世界地球科學界通行的 一個標準。 為了與聯邦地理資料委員會（ FDGC ）的地理電子元資料（ Digital Geospatial Metadate ）標準相容，新版的 DIF 做了不小程度的翻修， 總共含三十三個欄 位，文中有一個 DIF 和 Digital Geospatial Metadata 的欄位對照表。DIF 的另一個特色 是針對資料集或目錄（ Diretcory ）來處理，而非個別的資料或檔案， 因此也有資源指引 器的功能，本文也附有一個 DIF 和政府資訊指引服務（ GILS ）的欄位對照表。

　　　　　In this work, we introduce a metadata standard: the directory Interchan ge Format (DIF) developed by the NASA. It is not possible to directly retrieve the content of geospatial data, such as maps, because of its characteristics. Thus, geospatial data must first be cataloged before it can be organized. interchanged, and queried. DIF was designed for this kind of task and is now one of the accepted standards in Earth Science throughout the world. Inorder to be compatible with Digital Geospatial Metadata, another popular standard developed by FDGC, there are several new fields in the latest version of DIF. The number of fields is now thirty-three. One important Characteristic of DIF is that it focuses on data sets or on directories, rather than files, as its basic units; therefore, it can also function as an information resource locator, and is thus similar to GILS which was developed and adopted by the U. S. Federal Government. The mapping fields from the FDGC's Digital Geospatial Metadata to the Dif and from the Government Information Locator Service to the DIF arealso given in this work.