A more thorough explanation:

A shop steward is a union official who represents and looks after the interests of union employees. They oversee the performance of union contracts and ensure that the rights of workers are protected.

For example, if a worker feels that they have been unfairly treated by their employer, they can approach the shop steward for help. The shop steward will investigate the matter and take appropriate action to resolve the issue.

Another example is during contract negotiations between the union and the employer. The shop steward will be involved in these negotiations to ensure that the workers' interests are represented and that the final contract is fair and beneficial to the workers.