Example: Let’s say that there is a company which published magazines on the topic of finance operations in HR domain. Although, this magazine is supposed to be bought by only those people who work in this domain but these people may be from a large number of different organizations. Hence, this type of magazine is called horizontal publication.
Contrast with vertical publication: Those literature which is intended for the people of a particular industry is called vertical integration. For example, a magazines which publishes the latest events in the field of shipping is intended for all the people related to shipping industry. Hence, these magazines are called Vertical Publication.
Comparison between Horizontal and Vertical Publication: The biggest difference is the target customers. Although they may overlap to a certain extent. For example, a person who is working in the HR domain of a consulting company may be interested in buying the magazines which focusses on HR practices and consulting news both. Hence, the target customers can overlap for both type of publications. Similarly, a magazine may be both horizontal and vertical publication. If we take the same example, a magazine which publishes news about HR and consulting both may have both industry specific and across industries readers.