http://semver.org/

2. A normal version number MUST take the form X.Y.Z where X, Y, and Z are integers. X is the major version, Y is the minor version, and Z is the patch version. Each element MUST increase numerically. For instance: 1.9.0 < 1.10.0 < 1.11.0.

3. A special version number MAY be denoted by appending an arbitrary string immediately following the patch version. The string MUST be comprised of only alphanumerics plus dash [0-9A-Za-z-] and MUST begin with an alpha character [A-Za-z]. Special versions satisfy but have a lower precedence than the associated normal version. Precedence SHOULD be determined by lexicographic ASCII sort order. For instance: 1.0.0beta1 < 1.0.0beta2 < 1.0.0.

lib/whois/version.rb

@@ -19,10 +19,9 @@ module Whois
   module Version
     MAJOR = 1
     MINOR = 0
-    TINY  = 2
-    ALPHA = nil
+    PATCH = 2
 
-    STRING = [MAJOR, MINOR, TINY, ALPHA].compact.join('.')
+    STRING = [MAJOR, MINOR, PATCH].compact.join('.')
   end
 
   VERSION = Version::STRING