What is the difference between a resource and an activity?

This gives information about the difference between a resource and an activity.

What is the difference between a resource and an activity?

When you go to your course and turn editing on (button on the upper right), a link, "Add an activity or resource," appear at many places throughout the course page. When you click on this link you get a list of activities and resources that you may add to your course site.

Resources provide information for students. The resources are at the bottom of the list. Resources can be:

file --a document, picture, etc., from your own computer or a file you have posted previously
-- a handy way to organize multiple files
-- material (text, directions, pictures) that appears on your course page
web page -- a document that appears when students click on the link. The document can have images and/or formatting.
url = link to a web site -- a link to a site that exists outside of the Moodle program

Activities require student participation and submission of information. Most activities automatically create a entries in the Moodle gradebook program. Activities include the following:

Assignments: Only the teacher(s) can see what students submit in assignments. There different ways of submitting assignments:
Online text -- Students type responses directly into a web page.
Upload a file -- Students are expected to post one (or more) file (a Word, PDF, Excel, image, music file, etc.)
Off-line activity -- Students will not submit anything electronically. They will submit a paper, give a presentation, etc. A description of the assignment and an entry in the grade book can be made by the professor on the course site.
Chat -- An on-line chat involving students and, if desired, teachers. The default settings allow everyone to see everyone's comments in chronological order. Chats usually involve synchronous participation. Since the Google chat can include voice and video, the Google chat utility (sometimes done through Google Hangouts) may be a more useful utility.
Forum -- This is the Moodle term for discussions on various topics. With the default settings all students can see all comments and can reply to all comments and the comments are shown in nested form in chronological order with the name of the comment's author beside each comment. There are several different types depending on how many different topics are being discussed in one forum and who can introduce new topics. Forums usually involve asynchronous participation. Forums can be set so that email messages are sent every time there is a new entry in the forum (and this should be used sparingly). Each comment in a forum can have one document submitted as an attachment to the comment. Thus, forums can be used to allow students to see other students' work.
IPAL -- (In-class Polling for All Learners) Allows the teacher to give questions, one at a time, which all students will answer using laptops, tablets, smart phones, etc. The students' answers are displayed dynamically on the teachers computer screen and can be displayed (anonymously) back to the students. Questions can be multiple choice or free response. Free apps have been created for the Android and Apple smart phones. 
Quiz -- Each quiz consists of one or more questions that students answer. Only the teacher(s) can see the students' answers.
Wiki -- By default all students and teachers can see and edit everything that is entered into a wiki. It is good to use a wiki if you want students to collaborate on a document. The names of those that enter the material do not appear in the text displayed in the wiki. There is another part of the wiki which only the teacher can see. This part (wiki “History”) gives all the past versions and the history of all the submissions, including who is the author of each submission. The teacher can revert the wiki back to any prior version.

The Moodle program keeps a record of when each student participates in each activity and, for most of the resources, when the student looks at each resource. The teacher(s) can see this activity log for each student in his or her class.