What's the last letter in the Greek alphabet?
And the answer: Omega.
Developed between the 10th and 8th century BCE, the Greek alphabet is an ancestor of most European language alphabets. There are 24 letters total: the first three are alpha, beta, and gamma, while the final letter is omega.
While you might have heard the phrase "it's all Greek to me" in reference to something incomprehensible, this time it really is. Interestingly, the word "alphabet" comes from the first two letters of the Greek alphabet: alpha and beta. In fact, a staggering 30% of English words are thought to come from Greek. For example, the word "democracy:" from demos ("people") and kratos ("power"). Other words, such as those which begin "ph-" are almost exclusively derived from Greek: philosophy, physical, photo, phrase, and philanthropy are just several of examples of many which populate the English language (how many can you name?).
The Greek language is one of the oldest documented living languages in the Indo-European language family. In fact, there are written records in Greek that date back at least 3,400 years. The oldest record was found on a clay tablet dated between 1450 and 1350 BCE.
Due to its staggering age (and its many evolutions over the millennia), the Greek language was the first in many regards. Vowels, for one, were a novel introduction by the Greek alphabet. By contrast, the Phoenician alphabet, which the Greek alphabet is based on, uses only consonants. Even today, scripts like Arabic and Hebrew omit vowels entirely.
Learn more about the Greek alphabet here.