Streamm

Streamm is a programming language based on streamms, STDOUT is a stream, STDIN is a stream, the only data type is a stream, for example a "Hello" program (Hello World is hard):

Hello!|,

Basically, each line has 2 parts, the value and the name, formatted value|name. The special name , means STDOUT, and the value Hello! means to write Hello! to STDOUT

Interpreter

There is currently no interpreter for this language.

Is that it?

No. Thanks to filters, Streamm isn't as boring as it seems:

HiHiHi|,^{
  %pos|currentPos // %X means attribute X of the copying process, as the value is copied to the name, it checks this code block to make sure the character is valid
  currentPos mod 2|posMod2
  BE posMod2 // BE means return, if currentPos is even, then return 0, otherwise return 1, so only copy every other character
}

Output: iii