What counts as a programming language?

[NinjaNic]

Hey all! I've been looking at and trying to understand languages like Brainf**k, which were amusing yet complicated. So then, that made me think - what does a language have to have in order for it to be considered a programming language?

I quickly sketched this up, all it will do is print text into the console:

Module Module1

    Sub Main()

        Dim Code = IO.File.ReadAllText("C:\Path\testLanguage.txt")

        Dim IsPrinting As Boolean = False

        Dim i As Int32 = 0
        While i < Code.Length

            ' Print a letter.
            If IsPrinting Then Console.Write(Code(i))

            ' Check for commands.
            Select Case Code(i)
                Case "p"c ' A print command
                    If Not IsPrinting Then
                        IsPrinting = True
                        i += 1
                    End If
                Case CChar(vbCrLf) ' A new line command
                    If IsPrinting Then
                        IsPrinting = False
                        Console.WriteLine()
                    End If
            End Select
            i += 1
        End While

        Console.Read()
    End Sub

End Module

Which will read programs like this:

p Hello World!

(Obviously, that will print Hello World!)

EDIT: I updated it and gave it more commands.
p = Print
c = Comment
i = Wait for input, store it (as string, in the interpreter. Is that cheating?)
v = Print string variable

p Hello World!
p Am I a programming language?
c The current 4 commands are: c (Comment) p (Print) i (Input) v (Print Input)
p Type any string below:
i
p You typed:
v
p Goodbye!

Which would read:

Hello World!
Am I a programming language?
Type any string below:
> I typed this.
You typed:
I typed this.
Goodbye!

This language is by no means useable, but does even something like this get a title of being a programming language? Or does it need...which is what I'm asking, I don't know what it would need. So what makes a programming language a programming language?