Difference between "Parts" and "Materials" when viewing the map?

[Alcatraz]

Title. What do does each category include EXACTLY?

[ShiwaTheDrink]

Parts are the cogs you use to upgrade and build stuff, like the workshop for example. Materials refer to components and wood IIRC.

[Bobywan]

Materials = components or wood
Parts = "Parts" (the gear item) or Electric Parts.