Many bloggers forget to add alt and title tag in their images, they just upload an image to help a tutorial post or to make their blogs more beautiful but they don't add alt and title tag in their images, although the alt and title tag have many advantages, they are :
1. Alt tag makes your image like a text, so google will read your image as a text
2. Title tag helps readers to know about the image, because if readers put the cursor at image, they will read a text that is wrote in title tag.
3. Alt tag makes your blog become search engine friendly, so it is very good in search engine optimization.
4. Title and alt tag can help you to get traffics from google image search engine because google will find content in title and alt tag. So, put your keywords your title and alt tag and get traffic from your image.
So, they are reasons why you should use alt and title tag.
