diff --git a/base10.c b/base10.c
--- a/base10.c
+++ b/base10.c
@@ -47,7 +47,7 @@
     int i;
 
     if (argc != 2) {
-        printf ("Usage: %s [value]\n", argv[0]);
+        printf ("Usage: %s <value>\n", argv[0]);
         return EXIT_FAILURE;
     }