For content, what are the differences between nodes and terms
Nodes are content. Terms are for categorization of content, they are not content themselves.

Terms are part of taxonomies. Taxonomy is the science of classification.

The relation between nodes and taxonomy terms is that you attach taxonomy terms to nodes, to categorize the node. So if you have a blog node, you may have topics or tags, that would be attached to the blog node. You can use that to find all blogs of a certain category, or tagged with a given term. You can think of hashtags on common SNS sites as being like taxonomy terms. When you click on the hashtag, you can see all posts with that hashtag. The hashtag essentially categorizes the post.

You have listed some ways in which nodes and terms share technical implementations, such as having revisions. But how they are used is entirely different.