On this daf, we find days on which it is forbidden to fast.
The halacha is that a chosson and kallah who marry on Chanukah may not fast on the day of their wedding. And the same holds true for one who has yahrtzeit during these holy days. Even if he usually fasts on yahrtzeits, he may not do so on Chanukah.
One man who had a yahrtzeit on Chanukah learned that he could not fast, but he wondered whether he should make up the fast after Chanukah.
When this question was presented to Rav Shamai Gross, he ruled, “A chosson or kallah who were married during Chanukah or a person who has yahrtzeit during these holy days is forbidden to fast. In addition, they need not make up the fast after Chanukah” (Orach K’Halacha).