Although Gladys Kravitz was a relatively minor character on the show, the role was memorable enough that the term "Gladys Kravitz" entered the American lexicon, and is commonly used as a synonym for a nosy neighbor or colleague.
Try to control your temper. Remember, "Peace on earth, goodwill to men" includes witches.
In early episodes, the daughter is referred to in the credits as "Tabatha". In later episodes, however, the spelling of her name is changed to "Tabitha".
Whenever Samantha's cousin Serena appeared on the show, the credits for the episode listed the actress as "Pandora Spocks". This was Elizabeth Montgomery's idea as an inside joke. Elizabeth Montgomery played Serena.
Colorized versions of the black and white episodes have been syndicated. When the first DVDs were released in 2005, both black and white and color versions of the DVDs were available.