What is Image Optimization?
 

What is Image Optimization:

Image optimization is a function of lossy and lossless compression. Differences in image formats are due to the difference in how and which lossy and lossless algorithms are used to optimize the image.

Search engine cannot read the images without alt tags that means without alt tags search engine not recognize any image.The text in the alt tag is displayed in place of the image if the image can not be shown or is taking too long to load. Most of the major search engines are text-based, i.e they can not read images and videos.