To add abbreviation or acronym in HTML, use the <abbr> tag. Both abbreviation and acronym are the shortened versions and are represented as a series of letters. Some of the examples include, "Mr.", "MRP", "GMT", “NASA”, etc.
You can try to run the following code to mark abbreviation or acronyms in HTML
<!DOCTYPE html> <html> <head> <title>HTML abbr tag</title> </head> <body> <h1>Timings</h1> <p> We follow <abbr title="Indian Standard Time">IST</abbr> for our webinars. </p> </body> </html>