“K” is a more casual abbreviation. Using “M” as an abbreviation for thousand dates back to the Roman numeral system, where “M” was the symbol for thousand. It is still used in instances like CPM, or cost per thousand impressions.
What happens after 10k followers on Instagram?
Once you have 10k followers, Instagram will make it easier for you to get people to your website via Stories with the swipe up to link feature. Swipe up is the only way to get a direct link from your Instagram to your other web properties. And, it’s available in STORIES, if you have 10k followers.