A typical file I/O operation involves the following process.

1. Create or open a file. After the file opens, a unique identifier called a refnum represents the file.
2. Use a VI or function from the File I/O palette to read from or write to the file.
3. Close the file.

File I/O VIs and some File I/O functions, such as the Read from Text File and Write to Text File functions, can perform all three steps for typical file I/O operations. The VIs and functions designed for multiple operations might not be as efficient as the functions that perform individual operations.