Which language has the most number of letters?

This question can't be answered definitively because there are a few ways to interpret "letters":

* Letters in the alphabet: If we're talking about the number of letters in the standard alphabet, then English has the most, with 26 letters.

* Letters in a specific writing system: Some writing systems have more characters (letters) than others. For example, the Khmer language uses 74 letters in its alphabet, while Arabic has 28.

* Letters in a language's total vocabulary: This is much harder to measure, as languages constantly evolve and add new words.

So, the answer depends on your definition of "letters" and how you measure it.