"To collect certain resources you need the right tools for the job - you can't just go around punching trees!"
Tools are a loose category of items that can be equipped to use/interact with different objects in the game. Most tools are crafted at the Workbench however there are some special tools that have to be bought from NPCs.
These are tools used to chop/mine/gather various resources.
These are tools that interact with certain things, changing them or effecting them in some way.
Other items or objects loosely classed as "tools".