Terminal Powershell differences

When I type dir /A into terminal I get desirable output, but when I type the same to Powershell i get

dir : Cannot find path 'C:\A' because it does not exist.+ CategoryInfo          : ObjectNotFound: (C:\A:String) [Get-ChildItem], ItemNotFoundException+ FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.GetChildItemCommand

etc. Doesn't matter if I type dir /A . or dir . /A I thought that the Powershell is an extension of terminal so everything that works on terminal will be expanded on ps. How can I found the reason behind this behaviour?