An account (not to be confused with a user account) is the way to control access to your content in Content Controller. You'll create an account for each of your clients, and then add the content that you'd like to share with that client to their account. Accounts allow you to see at a glance what content has been shared with each client, and how that content has been used. They also allow you to change course configuration settings, error messages, and the player's appearance, for each of your clients.
A bundle is a way to package courses together into a group that's licensed as a single unit. For example, if you're selling courses, you can create a "Gold" bundle that includes every course in your catalog. Or, a "Golf" bundle that would include all of your golf-related courses.
Content can refer either to a course that has been imported into Content Controller, or to an equivalent that has been created from a list of courses all that present the same material in different languages. Courses are usually packages that have been published from an authoring tool as SCORM 1.2, any edition of SCORM 2004, AICC, cmi5, or xAPI. Each course or equivalent in Content Controller can be shared as a SCORM 1.2, SCORM 2004 3rd edition, or AICC package, or as an LTI tool provider, that can then be imported into an LMS and launched by a learner.
A course is a packaged content file (.zip). Content Controller supports the following types of standards/files: SCORM 1.2, SCORM 2004 3rd or 4th edition, xAPI, AICC, and cmi5.
In addition to regular courses, Content Controller can also deliver equivalents which are made up of regular courses with equivalent material presented in different languages. Let's say you have a course that you offer in English, Spanish, and French. The equivalent allows you to package the English, Spanish, and French versions of the course as a single file that you can share with your client. Equivalents can be shared with accounts exactly like regular courses, but when launched they present the learner with a menu of available languages. Selecting a language will deliver the regular course configured for that language.
A license is a set of limits on how content is used. These limits can be on the number of learners who can access the content ("up to 10,000 learners can take this course"), or on the amount of time that that content is available ("you have access to this course for 365 days"), or on a combination of the two ("up to 10,000 learners can take this course, within the next 365 days"). Content Controller allows you to attach a license to each course or equivalent individually as it is added to an account, or to an account as a whole.