For questions that concern constructing objects directly within some container object, as opposed to copying/moving the object into the container.
Use for questions related to the act of doing something in place, like for example inserting a new element in place.
For example, for an std::vector in c++, one could use std:emplace_back(), which is described like:
Inserts a new element at the end of the vector, right after its current last element. This new element is constructed in place using args as the arguments for its constructor.
