--- a/devel-versioning.rst	Fri Oct 21 13:18:18 2011 +0300
+++ b/devel-versioning.rst	Fri Oct 21 13:48:48 2011 +0300
@@ -71,6 +71,9 @@
 
 Prefixing version with a "v" seems to be less common.
 
+Versioning for libraries/modules/components.
+============================================
+
 Major version component.
 ------------------------
 
@@ -112,12 +115,24 @@
  * rc (release candidate) are believed to meet all of the criteria for release
    and can be installed on test instances of production systems.
 
+Versioning for products.
+========================
+
+Versioning for products differ from versioning for libraries.
+
+Product is a set of conponents fixed to some versions. Components can be
+switches as written for library versioning:
+
+ * Any fix release interchanged.
+ * Any minor release interchanged starting from some minor.
+ * Major release does not interchanged at all.
+
 Release build version data.
 ===========================
 
  * Build number.
  * Build date.
- * Build version.
+ * VCS revision.
  * Branch-tag used.
  * Overnight build (Y/N).
  * QA tested (Y/N).