Overlaying ad/redirect On website

Bot11 said:

I am a little new to the scene of SEO and advertising, but have some decent knowledge of web development/coding.

Anyways this is some thing always made me wonder whats its called and how its done ( I have a few ideas already.)

But sometimes when I visit websites no matter where I click on the website for the first time I get redirect to a popup/ad.

How are they overlaying the website with a clickable ad, like this.

Thanks for any replies or help.

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Met said:

it`s a simple link in the body tag. google fpr it and you will surely find some sources. you can also do it with cookies that it only open once per time frame set

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