電腦網路普及後，資訊的生產、傳輸、應用與服務蛻變。資訊系統的連線人人可 行，處處可及，在此環境下，資訊處理與服務的方式推陳致新。美國科羅拉多州研究圖書館 聯盟（ CARL ）的 UnCover 與 UnCover2 整合期刊論文索引、 目次、聯合目錄及文件傳輸 服務於一系統的方式已成為期刊處理與服務的新典範。本文敘述其發展的歷史、特點、檢索 功能、連線方法、文件傳輸服務及其對圖書館的衝擊。

　　　　　As the computer network grows and expands far beyond its previous confines. People anywhere can access the information system. This environment lead to new ideas for information processing and services. CARL's UnCover and UnCover2 are one of good examples. They integrate periodical index, table of contents, union catalog and document delivery service in one system and become new paradigm for periodical processing and services. This article describes briefly their history, characteristics, searching functions, connection methods, document delivery services and impacts on library.