Loading external data into a Go application is crucial for processing information effectively, and this involves reading data from files. By creating a `words.txt` file containing simple numeric values, the process begins with utilizing the `os` package from Go’s standard library to read the file’s content. The `readFile` function simplifies this by returning the file’s contents as a byte slice and any potential errors. Proper error handling is emphasized, although for initial experimentation, ignoring errors can streamline progress. Converting byte slices to strings allows for human-readable output, which enhances the usability of the data retrieved from the file. Understanding how to manage file input alongside effective data conversion is foundational for future programming challenges, such as counting the number of words in the file.