保存 and 保管: saving content and keeping items in custody
Compare saving files, preserving food, and storing baggage, without inferring condition or storage duration from a location alone.
Preserving a state or keeping content
保存, read ほぞん, means preserving a state or keeping content. 編集した文書を保存しました。 says that the edited document was saved.
食品を冷蔵庫で保存します。 says that food is kept in a refrigerator. The verb alone does not specify how long a particular food can be kept.
Keeping and looking after items
保管, read ほかん, means storing and looking after an item. 荷物は受付で保管しています。 says that baggage is being kept at reception.
大切な書類を金庫に保管しました。 means that important documents were stored in a safe. The physical documents and their storage location are both identified.
Overlapping objects and different uses
保存 and 保管 can overlap when documents or objects are kept. In a file operation such as 文書を保存する, the focus is retaining the content by saving it.
保存せずに画面を閉じました。 says that the screen was closed without saving. Editing a document does not establish that it was saved.
Can 保存せずに画面を閉じました。 be read as completed file saving?
Show the answer and why
No. 保存せずに means without saving and rules out completed saving in the described action.