The rexx scripting language provides:

- simple syntax that is easy to read
- small instruction set containing just two dozen instructions
- freeform syntax
- typeless variables
- character string orientation
- dynamic data handling
- no reserved keywords (except in local context)
- arbitrary numerical precision
- decimal arithmetic
- trailing zeros resulting from nonzero arithmetic operations are preserved
- a selection of builtin functions
- automatic storage management
- simple error handling
- builtin trace and debugging tools
- crash protection
- content addressable data structures
- associative containers
- straightforward access to system commands and facilities
- few artificial limitations
- simplified input and output facilities
- filename association
- unconventional operators
- no nudge operators
- no compound assignment operators
- no generic way to include functions and subroutines from external files
- no integral support for octal notation
- no integral support for regular expressions