Here are a few factors to consider:
* Number of letters: Some languages, like Khmer (used in Cambodia) have a large number of letters, around 74, but many are considered to be "digraphs" or "trigraphs", combining multiple characters to represent single sounds.
* Number of characters: If you consider Chinese or Japanese, they have thousands of characters. However, these aren't strictly letters in the same sense as the English alphabet. They are logographic, meaning each character represents a whole word or concept.
* Consonants and vowels: Some alphabets, like Arabic or Hebrew, have separate letters for consonants and vowels, but the vowels are often implied or written with diacritics.
To sum up:
* If you're counting the number of unique letters, then Khmer might have the largest alphabet.
* If you're counting the total number of characters, then Chinese and Japanese would have the most.
Ultimately, it's up to you to decide which criteria you use to define the "largest" alphabet.