The term netizen refers to people who are “citizens of the internet” or people that are regular users of the internet, specifically those that are active in online communities.
People who regularly go online to check their office emails or do online transactions such as shopping online or doing online banking are not considered to be netizens. Examples of netizens are those that are members or regulars of online forums, online multiplayer games, regular public chat room attendees, email groups, blog comment sections, file sharing sites, etc. The social aspect is a very important factor when quantifying a person as being a netizen or not.
A lot of netizens bond together to form groups with a specific goal or interest in mind. With the innumerable interests that bond people from all over the world you will find netizens flocking to groups with interests as trivial as having the same first names to more profound ones like charity groups aiming to raise awareness, support, and money for rare diseases.
Whatever, the purpose of the group may be these groups are great for filtering people that they form a niche market in the eyes of marketers and so become the target of online marketers. This is why large groups of netizens can expect to get sponsors during special events, companies interested in placing ads on the site, and even unscrupulous marketers posing as a fellow netizen on the group with the intent of “link dropping” or at least “spreading the good news” about a certain product or service.