- After one empty line, a detailed description of your changes
- the description most usually spans over multiple lines.
+ After one empty line, a detailed description of your changes
+ the description most usually spans over multiple lines.
+
+Wrap the lines to about __72__ characters or so. On an 80 column terminal,
+if we subtract 4 columns for the indent on the left and 4 more for
+symmetry on the right, we’re left with __72__ columns.
+
+Regarding the commit message body contents,
+Carl [has stated](http://article.gmane.org/gmane.mail.notmuch.general/504):
+
+> The single line summary is good about saying *what* the commit does,
+> but I always want to see at least one sentence about the *why* as well.
+
+### Activating default pre-commit hook
+
+Git provides a default pre-commit hook which, when activated, checks
+(at least) for whitespace errors (trailing whitespace and space before
+tab). It is better to notice this kind of "errors" early than have
+patch reviewers to mention about those.