An MSI file is a Windows Installer package file that contains installation information for a particular installer, including files to be installed and installation locations. It is a file that holds the information of the files to be installed and the path of those files. The .MSI file extension stands for Microsoft Software Installer, and it is a Windows Installer format that uses Microsofts Windows Installer service to configure installer packages, such as Windows applications or update packages. MSI files are used to install, uninstall, configure, and update programs on the computer. They are similar to .EXE files, but unlike .EXE files, MSI files always contain installers. To open an MSI file, you can double-click it, and it will allow you to install the Windows updates or program your MSI file contains. You can also use a 7zip to extract the .msi to see the content of an MSI file format, but you will only be able to see the files but not edit them. If you are looking into opening and quickly editing an MSI file, you can use the Orca tool, which is a free tool that opens the content of the MSI in a table view mode. MSI files are widely used by Windows users for software installations, and they are a target for inserting malware attacks.