1. Text Ad Unit
This is the normal ads you see on most pages with Adsense. This is also the most popular type of ads. With this ad you can customize its size and color. However, it is advised to change your ads format inside your Adsense account and paste it to your website rather than modifying it directly. As this is the most common type of ads, Google continually improves it to provide better “user experience”. Two of the last change is that now your visitors will have to click exactly on the ads as oppose to the background before. The other one is the introduction of expanded text ads where the ads has the arrow that you can click to reveal the rest of the ads.
2. Image Ad Unit
Image ads are ads that showing image rather than text. It takes only one advertiser per unit and is usually run with pay per impression campaigns rather than click. For some formats, the image ads can be selected to run in rotation with text ad unit. The selection on which one to display however, is done by Google. With this image ad you can only customize its border color and because the image is limited to 50 Kb in size it will not slow down your page loading time. The last improvement on this image ad is that Google is now allowing its advertisers to have animated image ads, however the size must also be less than 50 kb and can only loop three times. Google also claims that image ads will prove to be a “high performing option” compare to text ads. Image ads unit available on all text unit ads format except the 234×60 Half Banner, 125×125 Button, 180×150 Small Rectangle and the 120 x 240 Vertical Banner.
3. Video Ad unit
Video ads or Click to play video are ads unit available to your site only if you have selected to display image ads. The ads will be displayed as static image and visitors can click on the image to get the video ads playing. If the visitors click the ads for the second time or clicking the URL at the bottom of the ads, the visitors then are taken to the advertiser’s website. Only then you get the revenue for that ads and because of that you are allowed to click on the video ads ONLY to get it to play. It’s not advised however. By default your image ads will also be video ads and the only way to disable video ads is by using Competitive Ad Filter to block video ads from an individual advertiser or to use image ads that doesn’t support video ads which really only one format. At the moment there are not many video ads available for publishers so you are not likely to get video ads anyway. Video ads units are available on all Image ad units format except the 468 x 60 Banner.
4. Gadget Ad unit
Gadget Ads unit are like video ads but resembling minisites with video and links. Gadget ads units are available on all Image ads unit format, however, the because of the gadget which is mostly video size the most popular gadget size are the 336×280 Large Rectangle, 300×250 Medium Rectangle, 160×600 Wide Skyscraper and 728×90 Leaderboard ad formats. As with Video Ads unit, the only way to disable Gadget ads unit is by using Competitive Ad Filter to block Gadget ads from an individual advertiser or to not use image ads al together. Again just like Video Ads there are even less gadget ads available for publishers at this point in time.
With all of these units you can have maximum three ads units per page.
5 Link Units
Link Unit is a Google Ads showing link that when your visitors click will take them to a page displaying Ads optimized for the topic showing on the link units. This type of ads suit area where there are not many space is available. Note that you only receive earning when your visitors click on the Ads inside the result page not the link unit itself.
In Addition to the Ads unit above, you can have maximum three link units per page.
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