The main difference between XLSX and XLS is in how the data is stored. XLSX files are very similar in their functionality to their predecessor, XLS they can be used to create spreadsheets, charts and graphs, process mathematical formulae, and to share or analyse data.
XLSX was developed by Microsoft as part of their Office 2007 development and is now the default file format for Excel. This file format is a zipped Open XML-based file type, meaning it compresses or reduces the file size so that it can access stored data faster and be easily shared with other programs.
XLSX is a file type created using Microsoft Excel - part of the Microsoft Office Suite software.
