Update README.md

Author: CodeMaster7000

README.md

@@ -32,7 +32,7 @@
 
 Swift is a high-performance system programming language.  It has a clean
 and modern syntax, offers seamless access to existing C and Objective-C code
-and frameworks, and is memory safe by default.
+and frameworks, and is memory-safe by default.
 
 Although inspired by Objective-C and many other languages, Swift is not itself a
 C-derived language. As a complete and independent language, Swift packages core