The image above is from the website of Sharon Adams, which you can see here. She make beautiful tools from woods and metals as art.
Then here there is a link to a blog post on the use of locks, in specific on tool boxes.
To me, one is a set of tools for almost any purpose and one is a tool for a very specific purpose. Tools are for use, purpose and can do different things for different people. Locks are for hiding things away or keeping them safe, although they, as objects, are used they can cause that which is locked away not to be. I like that the author of the blog post has used a generic lock on his toolbox which simultaneously allows the box to be locked by the owner, and entered by anyone owns a similar key.