Image Optimization
1.    You images should be having Alt Text. Alt text is the texts, which is seen by search engines at images searches.
2.    You should use relevant Images, which teaches the topic clearly.
3.    Use low weighted images, your images should be less then 50 KB. Heavy images take much time to upload and it can be reason of low traffic, because user does not wait for uploading.

Why Alt Text?
You do not get any space in images to tell search engines about your topic. Alt text is just like a summery for your images. Search engine reads your alt text and give you opportunity in image searches. You should be very conscious about your alt text. Keep only essential less then 50 words in alt text. Do not do keyword stuffing in alt text.

How to write Alt Text?
<img src=”URL” alt=”keyword” />

Keyword – at the place of keyword, write your summarize keyword
URL – at the place of URL, keep your picture url.

This is called Alt Text Optimization.

Tips for Image Optimization
1.    Use always fresh picture, it means new picture.
2.    Do not give two urls in one alt text.
3.    Do not keep so many keywords in alt text.
4.    Use low weighted images.