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FAQ.md

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+# Frequently Asked Questions
+
+This page answers some questions that we frequently receive about the curriculum.
+If you have questions that aren't answered here, try asking through one of our [community channels](README.md#community).
+If it seems important enough or we get asked that question a lot, we will probably add it here.
+
+Alternatively, you could [contribute](#CONTRIBUTING.md) an answer yourself.
+
+## Contents
+
+- [Are Coursera courses free to access?](#are-coursera-courses-free-to-access)
+- [Does every resource in the main curriculum have to be free?](#does-every-resource-in-the-main-curriculum-have-to-be-free)
+- [In what order should I take the courses?](#in-what-order-should-i-take-the-courses)
+- [Is it necessary to purchase the Verified Upgrade for edX courses?](#is-it-necessary-to-purchase-the-verified-upgrade-for-edx-courses)
+- [Why do you recommend skipping the second half of CS50?](#why-do-you-recommend-skipping-the-second-half-of-cs50)
+- [Why doesn't the curriculum cover/ignore topic X?](#why-doesnt-the-curriculum-cover-ignore-topic-x)
+- [Why is the curriculum missing some pre-requisites?](#why-is-the-curriculum-missing-some-pre-requisites)
+
+## Questions
+
+### Are Coursera courses free to access?
+
+Some courses that require payment to access probably do exist on Coursera, but we don't put those on our curriculum.
+All Coursera courses that we put on the curriculum must, at minimum, be **free to audit**.
+For some courses, all course features are available for free;
+for others (especially those that are part of a specialization), you may only be able to access the lecture videos.
+(If you find the policies have changed for any courses on our curriculum, please tell us!)
+
+Unfortunately, for some courses, Coursera's interface is [very aggressive](https://darkpatterns.org/) about convincing you that you have to pay.
+
+You may see something like this on the course page:
+![Free Trial](http://i.imgur.com/KKDtDBF.png)
+
+When attempting to enroll in such a course:
+- Click the blue "Enroll" or "Enroll Now" button.
+- A pop-up will appear.
+- **Do not click** "Start Free Trial", unless you do want to pay.
+- Find the text that says "Audit this course" at the bottom.
+- Click **Audit**.
+
+![Audit this course](https://user-images.githubusercontent.com/3349406/27321369-95ca12e6-55cc-11e7-9b5c-f8fedd8fd643.png)
+
+### Does every resource in the main curriculum have to be free?
+
+Yes, because we have to draw a line.
+As soon as we require paid resources in the main curriculum, we might as well tell people to pay half a million dollars to attend a university.
+We are an Internet-based community of learners, not a business, so free is the most sensible price and ensures that the only price you need pay is the price of Internet access.
+
+At the same time, we recognize that education is scarce resource and therefore requires payment to instructors to make it sustainable in the long term.
+Therefore, we respect the business model of websites like edX, which make their materials free but with some paid add-ons, like official certificates or extra interaction with course instructors.
+
+So we only require that the *learning materials* of a resource be free to access, not that every possible add-on be free.
+It would be ideal if graded assignments were always free but if we had this requirement, we would have to exclude any resource that doesn't have graded assignments at all.
+Plus, there are other ways to get feedback on your work, and OSSU is a do-it-yourself education.
+
+### In what order should I take the courses?
+
+You have a few different options:
+- You can progress linearly from top to bottom of the page.
+- You can progress linearly through each individual section, but studying different sections in parallel.
+- You can design your own custom progression using the pre-requisites to guide you.
+
+We have designed the curriculum to work for any of the above three styles.
+
+### Is it necessary to purchase the Verified Upgrade for edX courses?
+
+If you just want to watch the videos, it is never necessary for any edX course on our curriculum.
+
+CS50 doesn't use edX's grading system; it grades all assignments for free.
+
+The [Software Development](https://www.edx.org/micromasters/software-development) courses have mostly free quizzes and assignments, but their Final Projects will only be graded by a human if you pay.
+
+### Why do you recommend skipping the second half of CS50?
+
+The strongest and most useful part of CS50 is the part where they teach C.
+We wish to retain this in the curriculum for now because it is one of the few chances the student has to play with manual memory management in a (relatively) low-level language.
+Everything after that gets a bit too easy and shallow, to the point that we believe the student's time will be better spent in MIT's Introduction to Computer Science course.
+
+That being said, feel free to finish CS50 if you like it and want to.
+But don't skip the MIT Intro course.
+
+### Why doesn't the curriculum cover/ignore topic X?
+
+We have several goals that we have to balance:
+- Ensure students learn the timeless principles of computer science in the best possible way, pedagogically speaking.
+- Ensure students are given sufficient knowledge of today's systems to be employable in the near future.
+- Ensure students are exposed to enough cutting-edge knowledge that they won't be left behind when technology changes, which it always does.
+- Keep the curriculum brief enough that it can be completed in a reasonable amount of time.
+
+Therefore, not everything can be included, but we strive to be eclectic so that students are both employable and well-armed for change.
+
+### Why is the curriculum missing some pre-requisites?
+
+The curriculum assumes two things:
+- You are reasonably fluent in English.
+- You have gotten through a standard high school curriculum that included physics and pre-calculus.
+
+Without these assumptions, the curriculum would be out of control with trying to fill in your knowledge gaps.
+But those who for whatever reason didn't get all the way through high school math and physics are in luck: you can find the content you need on [Khan Academy](https://www.khanacademy.org/).
+
+Of course, if you find that the curriculum is missing a pre-requisite for a course that isn't part of a normal high school curriculum, please let us know!