diff --git a/D/cov.md b/D/cov.md
index 6dec151..ed6f33b 100644
--- a/D/cov.md
+++ b/D/cov.md
@@ -31,4 +31,6 @@ username: "JoramSoch"
 
 $$ \label{eq:cov}
 \mathrm{Cov}(X,Y) = \mathrm{E}\left[ (X-\mathrm{E}[X]) (Y-\mathrm{E}[Y]) \right] \; .
-$$
\ No newline at end of file
+$$
+
+Variables with a covariance of zero are called uncorrelated.