What is the relationship between the letters samekh and sin? Did they ever have distinct sounds? Why do they exist as separate letters?
Why does Hebrew use the same letter to represent two different sounds: shin and sin? As far as I know, with the exception of when using a dagesh kal, no other Hebrew letter has this property.
Avarham Avinu was originally Avram - and Hashem added the letter Hai to his name and changed it to Avraham. Why from all letters was the letter Hai added?
Which letter of the alef-beis isn't found in bentching and what is its significance?