diff --git a/blocks.h b/blocks.h
index 834dae3..cb60a91 100644
--- a/blocks.h
+++ b/blocks.h
@@ -5,7 +5,8 @@
 
 /* If interval of a block is set to 0, the block will only be updated once at startup.
  * If interval is set to a negative value, the block will never be updated in the main loop.
- * Set signal to 0 if signalling is not required for the block.
+ * Set pathc to NULL if clickability is not required for the block.
+ * Set signal to 0 if both clickability and signaling are not required for the block.
  * Signal must be less than 10 for clickable blocks.
  * If multiple signals are pending, then the lowest numbered one will be delivered first. */