if you are advertising for someone:
why would you focus on using images to drive? images can add flavor to your website, but use them sparingly and focus on your content. whenever you use the images, it is often recommended to embed a link within - whether they link internally or externally. not linking images is a wasted opportunity since you are going to be using them anyway - might as well benefit from an added link tag.
from an adsense perspective however, image ads don`t do as well as text ads. there is much to be debated on the why, what, when etc. basically the reasons why it is what it is...here is an article that can get your thoughts rolling however on this subject:
if you want to advertise:
image ads can be more expensive as they take up much more space. also, many people are just over banner and image campaigns, though you can make the same argument for text ads and say that video ads are the next big trend.
all that said, banner ads are still quite effective - depending on your business and where you advertise. you can often target a niche, focused customer base with banner ads if you know what sites they frequent. with google, the good thing is that everything is context based, so they will automatically pair your ad up where they see it fitting best.
the choice is yours but in the end image ads just have not proven to be as effective as text ads
good luck - and please let us all know what works for you and what does not!
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