Write Bracmat expressions in the upper text box.
After pressing the evaluate button,
the result of the evaluation of your expressions
will eventually appear in the lower text box.
Bracmat is a programming language for symbolic computation with an exquisite programming construct for pattern matching. Read the documentation, and see many more examples on rosettacode.org.
Full, more than 100 times faster versions of Bracmat compiled and linked for Windows, macOS and Linux, together with the C source code, can be found on GitHub.