An ads agency can be defined as a company that creates, manages, and plans all points of a client’s ads. An advertising company may concentrate on a specific area or could be a full provider agency that provides public relation facilities. There are three types of advertising businesses; Above the Line, Below the Line, and Through the Line. ATL are large companies that handle prime account and create countrywide and foreign advertising campaigns for the consumers. BTL handle smaller media placement while THL is a mix of ABL and BTL.
Here are the biggest ads companies worldwide.