Both MSI and EXE are file types used by Windows operating systems to install and run programs. They perform essentially the same task, but they do so in a slightly different manner.
The "EXE" is short for "executable," and this file type has the ".exe" extension after the file name. For example, "install.exe" would be an installation executable file. Executable files can install an application, or run an application that is already installed on your computer, and they are primarily associated with Microsoft Corp.
An "MSI" file is a Windows Installer File, and it is also associated with Microsoft Corporation and the Windows operating system. This type of file has the ".msi" extension following the file name, such as "install.msi," and it works similarly to an EXE in that it is responsible for installing programs on your computer.
The main difference is that an MSI file is designed for a silent (unattended) installation. This means that it contains a record of keystrokes and clicks necessary to completely install the file. Conversely, an EXE file might require the user to click "OK," or "Next" or choose options over the course of the installation.