Images are definitely a must-have when you are creating web copy or a blog article. It is an awesome way to illustrate a story with long content.
In regards to SEO, images provide a lot of value to your on-page content because images have title tags, meta description, and alt-tags that tell Google exactly what the image is about. A great way to boost your content for that page is blending in the different SEO keywords into your images as well.
According to Yoast, follow this image SEO checklist outline because it has important factors one must consider when inserting an image into your content.
Use a relevant image that matches your text.
Pick the right file name for your image. The file name should match the content of the image. This helps Google with understand exactly what is within the image.
Make sure image dimensions match the image size as displayed. I know this may seem trivial, but if your image files state it is 200×200 pixel size, but it is actually 1280×670 pixels.
This is will impact your page load speed because everything that happens behind the scenes is based on mathematical formulas and principles.
Image size matters when the UX factors in how much processing power is needed to load your image. If your code states the image is small but it is actually a very large, it will actually slow down the loading speed. This will cause you to lose traffic to your website. Because who likes a slow webpage? I don’t.
Use srcset if possible. This tool optimizes the size of your image when different screen sizes are used to view your content.
Reduce file size for faster loading. There are a lot of tools that can be used to compress the images on your server. Most images don’t need to be massive files in order to view it correctly on a webpage.
Add a caption for easier scanning of the page. This is pretty self-explanatory. Captions are typically a view words in a string that appears to be the title for the image.
Use an image alt text, the title text is optional. I highly recommend adding alt text to every image. This is where you can insert long tail keyword phrases or LSI keywords.
Alignment of your content. Aligning your images correctly will create a better reading experience for your readers.