IDK is an abbreviation of the phrase “I don’t know,” and it be can spelled capitalized or uncapitalized. According to Grammarly, the abbreviation has been around since sometime around 2002 (or even earlier), when it appeared in text speak. On Urban Dictionary, the phrase is defined as the shorthand form for “I don’t know” in a comment posted in 2003. The abbreviation is most commonly used and understood by younger generations (think generations Y and Z), but don’t bet that someone who isn’t as tech- or text-savvy will understand what the phrase means. According to Google Trends, IDK is most often used in the United States, Poland, and Moldova. The usage of the term really began to skyrocket on the web in 2007. The abbreviation’s popularity rose again with another significant hike during the current global pandemic with a focus in memes, possibly reflecting people’s confusion and uncertainty over the state of society during the lock-down period.