I am reading the User Guide. Page 38:

We investigated a number of different options; whether to extend the current CMD.EXE syntax or to modify the current Visual Basic to better enable an interactive use. After looking at many different possibilities, we decided that a new language that was built from the ground up would be best because it would enable us to provide a more consistent environment. We were inspired by concepts in the UNIX shells; other scripting languages such as PERL, PHP, PYTHON and programming languages like C# to create a consistent, intuitive language that is an interactive environment.

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Similar to the UNIX model, the majority of users will find that the use of commands is sufficient to accomplish what is required. However, there are conditions when existing commands do not provide the required functionality. In these cases, there are generally two choices. First, if the functionality is able to be composed, create a script to provide the necessary functionality. Second, create a new command to provide the needed functionality (much in the same way that the functionality of text parsing utilities for the UNIX system have increased over time and is arguable why PERL, TCL, and other scripting languages developed). Unfortunately, the complexity of creating a new command can be high, and in some cases, the required tools (such as a compiler) are not available.

For the records... Perl is named 6 times. C#, 14. Java, 0. TCL, 2. Python, 2. Ruby, 1.