Title tag in image

Hello friends,
what is the use of title tag in image ?, it is different to ALT tag or equal it, means what is the role of title tag in image ? , We should use it or not.

Thanks

With an image, the title and alt attributes have different functions.

‘Alt’ is short for ‘alternate text’, and means text that should be used as an alternative if the image is not available (eg images turned off, file doesn’t load, using a browser that doesn’t support images). The text you use should fulfil the same function as the image, but need not be a full description. You must always give alt text but where the image is purely decorative, alt=“” is a sensible option.

‘Title’ text appears as a ‘tool-tip’ note when you hover the mouse over the image (actually it applies to any element, you can put a title on anything and get the same effect). This gives additional information to people who can see the image, but you can’t guarantee that they will hover the cursor over the image for long enough to see the pop-up so you shouldn’t put any vital information there. If there is no need to give this additional information, you can leave out the title altogether.

The confusion between the two has come up because IE wrongly gives a tool-tip with the alt text in, if there is no title given. It shouldn’t do, but it does.

The Alt attribute of the img tag is good to be referenced as a description of the image, along with the keyword of the text in this reference.