what is use of alt=""

Answer 1

it is better if u use it because it helps search engines also in identifying the content of the image there by helping in search engine optimization

Answer 2

if for some reason the image cannot be displayed then the viewer of the page will get information about the image.

Answer 3

is it necessary to use this?

Answer 4

No it is not necessary but like said it does things that are handy

Answer 5

Alt attribute specifies an alternate text for an image, if the image cannot be displayed.