JSON and XLS explained
JSON represents structured data as nested objects and arrays. It came from JavaScript but is now the default interchange format for essentially every web API.
The pre-2007 Excel format is a binary structure limited to 65,536 rows and 256 columns — limits modern datasets routinely exceed.
- Where JSON files come from
- APIs, configuration files and application data exports.
- Where XLS is used
- Spreadsheets from Excel 2003 or earlier, and some legacy export systems.