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In computer science, persistence refers to the characteristic of state that outlives the process that created it. This is achieved in practice by storing the state as data in computer data storage. Programmers have to transfer data to and from storage devices and have to provide mappings from the programming data structures to the storage device data structures via serialization of data and structure to formats compatible with the storage. Picture editing programs or word processors, for example, achieve state persistence by saving their documents to files. == Orthogonal or transparent persistence== Persistence is said to be "orthogonal" or "transparent" when it is implemented as an intrinsic property of the execution environment of a program. An orthogonal persistence environment does not require any specific actions by programs running in it to retrieve or save their state. Non-orthogonal persistence requires data to be written and read to and from storage using specific instructions in a program, resulting in the use of ''persist'' as a transitive verb: ''On completion, the program persists the data''. The advantage of orthogonal persistence environments is simpler and less error-prone programs. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Persistence (computer science)」の詳細全文を読む スポンサード リンク
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