What is vertical specialization and what is horizontal specialization

vertical specialization：
Delegation of responsibilities and duties to others within the same line of authority. Vertical specialization occurs as an organization grows, becoming more complex and requiring additional personnel to cope with the additional workload.

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horizontal specialization：
Organizational process whereby a single management function, such as recruiting, is divided among one or more subordinates; also known as functional management. Horizontal specialization usually occurs because growth in an organization requires additional management coordination and control.

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