diff --git a/README.md b/README.md
index fc6360c..e2e24fb 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,13 @@
 # Brainfuck_PY_interpreter
  
+Brainfuck interpreter
+
+> increment the data pointer (to point to the next cell to the right).
+< decrement the data pointer (to point to the next cell to the left).
++ increment (increase by one) the byte at the data pointer.
+- decrement (decrease by one) the byte at the data pointer.
+. output the byte at the data pointer.
+, accept one byte of input, storing its value in the byte at the data pointer.
+[ if the byte at the data pointer is zero, then instead of moving the instruction pointer forward to the next command, jump it forward to the command after the matching
+]
+] if the byte at the data pointer is nonzero, then instead of moving the instruction pointer forward to the next command, jump it back to the command after the matching [.