ScummVM is a free and open source software that allows you to run certain classic graphical point-and-click adventure games, assuming you have their data files. In other words, it replaces the original executables of the games, allowing you to play the games directly (without DOSBox like emulation) on new systems.
Unlike DOSBox, ScummVM provides custom emulation for each game and not for DOS itself. Of course, this means ScummVM emulates games in an opt-in fashion. That is, the developers choose which games would be supported, as opposed to DOSBox in which you can (at least try to) run anything that runs under DOS.
Since ScummVM uses the same license as DOSBox, is almost as unintrusive in its installation (the general configuration file must be put in one of Windows' special folders), and is just as cross-platformed, once a game is within the limited range of games supported by ScummVM, it is pointless to run it in DOSBox anymore.