Promotions in government jobs generally happen through seniority, departmental exams, or a mix of both.
Many posts have a defined promotion channel — for example, a clerk may become an assistant after a few years of service.
Departmental competitive exams let eligible staff move to higher posts faster.
Promotions also bring a higher pay level under the 7th Pay Commission.
The exact rules are laid down in each department’s recruitment and promotion regulations.