The need for accumulation and codification of vast amounts of information pertaining to collections in art or historical institutions has led to the consideration of computers for museums. The interactive computer gives the user the ability to manipulate data as requirements change or become clearer. Choosing the computer system best suited for an institution is discussed. The structuring of an information system, input of data and instructions, the storage, retrieval and output of information, and the sorting, comparison and addition of data are topics covered by the author. The use of convenient computer language is stressed. Types of data processing: batch and on-line (or real-time) processing, and their comparable merits are mentioned.