In layman language, an acronym is a word formed by taking letters of each word in a phrase to form an abbreviation. Acronyms are a subset of abbreviations i.e. abbreviation is a shortened form of a word.
The <acronym> tag isn’t supported in HTML5 and is deprecated now. Do not use. To add abbreviation 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.", "IST", "MRI", “NASA”, “ISRO” etc.
You can try to run the following code to add abbreviation in HTML.
<!DOCTYPE html> <html> <head> <title>HTML abbreviation</title> </head> <body> <h1>Space Exploration</h1> <p>US Space Explorations are governed by <abbr title="National Aeronautics and Space Administration">NASA</abbr>. </p> </body> </html>