Digital advertising often refers to video, display and paid search advertising delivered on desktop and mobile devices (i.e. smartphones and tablets). However other digital advertising media also exist, including: VOD (video on demand) advertising consumed on TV sets, digital OOH (out of home) advertising served on digital billboards and radio advertising served on digital radio. Consequently, it's important to clarify exactly what media are being included when someone refers to "digital advertising" and to not make assumptions.
A key attraction of digital advertising is its potential to target advertising to specific people. Publishers (i.e. website and platform owners) along with DMPs (data management platforms) can use data gathered from people's online behaviour and combine it with other datasets to build up a picture of each user, thereby allowing advertisers to target people with specific profiles or characteristics. However, the data is far from perfect and is susceptible to inaccuracy caused by incomplete data, cookie deletion/blocking and a frequent inability to link a device to a person.
Digital advertising also has challenges from issues such as fraud (where fake sites and bots are set up to generate clicks), brand safety (where ads are placed next to inappropriate content) and viewability (where advertisers sometimes pay for ads that are not seen or are only seen for very short fractions of time).
Digital advertising is a continuously evolving area with new solutions and challenges and new platforms and ad formats emerging frequently.