<a> is used for creating hyperlink.
Any thing which is placed between <a> and </a> becomes a hyperlink and when it is clicked , it is redirected to the location put in href attribute of <a> tag.
e.g. <a href = “http://www.google.com”>google.com</a>
So, if an image is placed between <a> and </a>, then it behaves as a link and when the image is clicked, it will redirect to the location put in href attribute of <a> tag.
<!DOCTYPE html> <html> <head> <title>Image as Link</title> </head> <body> <p>Using Image as Link. Click on the below Image</p> <a href="https://www.google.com"> <img src="java-e1464184781120.png" width="150" height="150"> </a> </body> </html>