What is the most commonly used letter in the English language?

The most commonly used letter in the English language is the letter 'E'. This letter appears in almost 12.7% of all English words, making it the most frequently used letter in the English alphabet.

One of the reasons for the popularity of the letter 'E' is that it appears in many common words such as 'the', 'be', 'me', 'he', and 'she'. In fact, the most common word in the English language, 'the', contains the letter 'E'.

It is also worth noting that 'E' is the most commonly used letter in several other languages, including French, Spanish, and German.