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Windows environment variable: PATH

PATH consists of a list of directories, separated by semicolons, that are searched for executables or executable scripts (whose suffixes is listed in PATHEXT) when trying to execute them without stating their location with an absolute directory path.
After installing Windows 10, the components seem to consist of the following directories:
On a notebook, I also found this directory: C:\Program Files (x86)\ATI Technologies\ATI.ACE\Core-Static.
The value of Path is a combination (concatenation?) of HKLM\SYSTEM\CurrentControlSet\Session Manager\Environment and HKEY_CURRENT_USER\Environment and the value of Path under HKEY_LOCAL_MACHINE\Software\DefaultUserEnvironment
The cmd.exe command start is able to locate executables (binaries) that are not found via the PATH environment variable. These applications need to be registered under the registry key HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\App Paths.

PowerShell

In PowerShell, the individual directories in the PATH variable can be printed each on its own line with one of the following two commands: 
PS C:\> $env:path -split   ';'
PS C:\> $env:path -replace ';', "`n"
The PATH environment variable might contain a tilde (~) which is used to shorten long paths: 
PS C:\> $env-temp
C:\Users\DOMA~1.REN\AppData\Local\Temp
At times, the value of $env:temp needs to be expanded to the real path. This is possible with 
PS C:\> [System.IO.Path]::GetFullPath($env:temp)
C:\Users\DOMAIN.Rene\AppData\Local\Temp

See also

where.exe displays the directory of an executable that is located in any of the directories listed in PATH.
paths.ps1 is a PowerShell script that prints the individual components of the PATH environment variable to the console.
Windows environment variables

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