All operating systems and applications support selection with point/click or aim/touch. Most also support multi-selection to choose lists, icons, and objects. If the items aren't contiguous (i.e., there are item(s) between A and B), then using command-click to make that multi-selection is one of the more common ways to multi-select on a desktop OS.
If there was no keyboard on a laptop computer, how can this interaction be supported?
How might we produce the best interaction model for the selection multiple items, but using only a mouse (point/click)?
I separated the current type of multi-selection into 3 categories to sort them in my research.
I also grouped the interactions by view types.
I conducted research to determine interactions, products and systems utilizing these interactions, and pros/cons of each.
Given my limited time to complete the project, I explored the preferences of participants in a rapid user discovery research session.
Based off my (mock) user research, the best solution appears to be based on context and preference.
Using all of the insights and research, I produced a design concept: Use of gestural selection in design tools (in this case, Illustrator).
If more time were allotted, I would have given the participants interactive prototypes to have them complete specific scenarios. Then, I would probe them for subjective opinions and perform a heuristic evaluation to provide another iteration on the design.