I'll combine what I've learned from the interview we did and from sir Oli's discussion.

There are three types of managers namely Executive, middle and operational managers. Executive being the highest position of a manager and operational for the lowest. Each managers have their own responsibilities.

Executive:
These are the people like CEOs, presidents and the like. Yes, they don't have much work. Just sit in the offices, and talk to people about the progress from time to time. However, people doesn't see their real job. Their real work is done around once or twice a year. Where they plan on annual progress of the company or the direction of the company.

Middle:
Middle management is the middle class of managers. Their job is to plan and manage the resources of the company and make the most out of them. Just like executive management, they plan for the future and not for the present.

Operational:

Operational management involves work regarding the management of the day's outcome. They make sure that their team meets the requirement or the expected outcome for the day. Unlike middle and executive management, they plan for now and not for the future.