A typical need of any software application is to input/output data by reading/writing data files or data streams or by querying/manipulating a database. Regarding files and streams, unstructured data, or even binary data, is hard to manipulate, and so they are not recommended.
Also, proprietary data formats are not recommended because of the vendor lock-in risk, and so only standard data formats should be used. Fortunately, there are free Rust libraries that come to the rescue in these situations. There are Rust crates available to manipulate some of the most popular file formats, such as TOML, JSON, and XML.
In terms of databases, there are Rust crates to manipulate data using some of the most popular databases, ...