In PowerShell 2.0 on Windows 2008 or Windows 7, there were only a handful of modules installed by the operating system, so knowing what modules were present and what commands were included in each module made sense. In PowerShell 3.0 with the CIM modules, the number of commands available jumped over 2,000, and it became unrealistic for users to be able to remember which of the scores of the modules contained in the commands were needed. To overcome this issue, PowerShell 3.0 introduced the concept of autoloading the modules. In PowerShell 3.0, if you reference a command that is not present in your session, PowerShell will look through the available modules (and in PSMODULEPATH), find the module that contains the missing command, and import it silently for you. This means that if your modules are installed in the correct directories, you don't have to use the Import-Module statements anymore.

When I first heard about module autoloading, I didn't like it. I thought...