Similar to opt-ins, permission marketing is a type of registration technique as per which users are notified and asked for consent before being contacted. Permission marketing was developed and conceptualized taking into account the fact that advertisements are increasingly becoming disruptive and are disturbing the flow of web surfing for internet users. Such disruptive ads had to be done away with and thus a solution was formulated in terms of permission marketing. Ads will thus be received in a much better manner by the user if the permission is first sought out by the advertiser. Search engine marketing can be viewed as another form of permission marketing wherein only those advertisements are shown to users which pertain to the content that is already being searched for.