diff --git a/php_keywords.txt b/php_keywords.txt
index 7788890..40c0b85 100644
--- a/php_keywords.txt
+++ b/php_keywords.txt
@@ -1,3 +1,10 @@
+# This is a list of php7 internal keywords and their 3 base64 fingerprints.
+# Some patterns are too short to be useful with scan.php.
+# All base64 patterns 3 characters or less have been commented out.
+# This file should be ready to use in place of patterns_raw.txt
+# Expect false positives and slow scan speeds.
+# Use this pattern file on known malware to find new patterns.
+
 # "__halt_compiler" in base64
 X19oYWx0X2NvbXBpbGVy
 9faGFsdF9jb21waWxlc