Hello Dopani, you may not realize how much you can increase traffic to your page with the optimization of the images that you use in the page. For example if you see Google has special search with Google images.
Fortunately it's easy than you think to optimize your images within your site to work in Image SEO Optimization as it is wide known.
Alt Text
When you see a picture with a watch directly you can understand in what state the image and by extension article that includes the image.
The problem is that this cannot be directly identified by the search engine spiders. However, there is a way to help search engines to understand the topic of our image. Call it Alt text (Alternative Text)
What is the Alt text?
Very quick but comprehensive answer is html command that makes the search engines to understand the subject of the image we use in some text. And written alt = "and here is alt text".
File Size
All most know that the loading speed of the site is a determining factor in SEO. And one of the reasons that lingers a site loads are very heavy images used. We can have very good quality pictures but with the right amount needed for the internet.
There are online tools to help us to shrink this partition the weight of an image but to keep the quality of. Two of them are Picnik and Image Optimizer is free, of course.
Good is when we use an image in 2 different sizes to make sure to bring a picture that size would be nearby and in 2 sizes that we want. This why? Because when the browser does this to changing i.e. picture size have a long delay in the loading of the page.
File Name
A third step and very basic is the name of the file (image) i.e. "picture_name.jpg" And here you should include a proper name that betrays the image content. It is good after talking about on page SEO in the name to include the keyword that we work our article. For example: seo-forum .jpg is very correct name if our article talks about seo forum. Among the words we put the symbol "–" because the machines do not have the sense to divide words.
Captions
Image caption has no direct relationship with the on page seo but with the Bounce rate of a page. The caption to an image works as a title we can to keep the reader with the very clever caption after after first glance that goes on the image immediately after the eye go in the caption, and then decided to move to reading the article.
These are some my simple tips about how to optimize images for SEO and improve your traffic with search engines like googles, bing..etc. Hope it helps!