This paragraph in particular is a great summary of what the term means
The people’s democratic dictatorship uses two methods. Towards the enemy, it uses the method of dictatorship, that is, for as long a period of time as is necessary it does not permit them to take part in political activity and compels them to obey the law of the People’s Government, to engage in labour and, through such labour, be transformed into new men. Towards the people; on the contrary, it uses the method of democracy and not of compulsion, that is, it must necessarily let them take part in political activity and does not compel them to do this or that but uses the method of democracy to educate and persuade. Such education is self-education for the people, and its basic method is criticism and self-criticism.