Images and the embedded videos are two major things which increases the load time of the website and now a days load time of the website also affects in the SEO if you have a highly optimized website which have a faster loading speed with awesome content then it will get in the top ten results.
Its also decreases the bounce rate of your website so that you can get more readers and good number of page views from the existing content. If your blog is hosted on the blogger then its most helpful for you because whenever you open your blog (which is hosted on the blogger) it loads all the images of the posts like you have set 6 posts on the home page and you have used 20 images in the last 6 posts then whoever opens your blogger blog then it will load all the 20 images and suppose the average size of every image is 100KB then ? the total home page will become 2000KB and it will also load other CSS and scripts and eventually your home page will become 2MB+ size and for those who have lower bandwidth it will take more time to open your blog.
If you have hosted your blog on the WordPress content management system then it will not load all the images in the home page and still you can optimize the images for your site.
All you need to optimize your image for web is Photoshop! just download it and then start using it and if you want to learn Photoshop online then here is the blog of Photoshop.
Now first of all make the image you want to add in to your website/blog and never use copied image and if you use somebody’s image then give them a credit.
After making your image in the Photoshop don’t save it directly! it will give you the best quality so the size of image will be big so you have to tell the Photoshop that i want to use this image for the web so how to tell it?
After making image just go to the File and then select save for web.. and then one window will popup and then set the image quality and image format and then change the quality of the image.
Now simply save the image and you will get the optimized version of image and which is best suitable for web. And now you can see that the actual size of the image is 535KB and the optimized version’s size is 93.7KB.
So it have decreased more then any image optimization can do. if you have any question about this then feel free to ask!