While the educational use is the most common literary "content" for the string "met.rar," it can also refer to scientific and professional terms in different formats:

Students are often asked to identify the meaning or context of this specific phrase within a given story to test their reading comprehension skills. Other Technical and Scientific Associations

In the 2023 Singapore Chinese Girls' School End-of-Year Examination and associated activity books , "MET-RaR" appears as a "secret code" or a distinct sound made by characters in reading comprehension passages.

It is often used as a greeting or a playful exclamation between friends (e.g., characters like Sherlock and his friends).