Computer Systems

1. Bits and bytes

   Start here

   Convert two’s-complement and IEEE-ish examples at a small width, and say what overflow does.

   Take this classAlready know this

2. Machine code

   After Bits and bytes — test out to unlock

   Read a short assembly snippet (moves, calls, stack) and say what the C that produced it was doing.

   Test out to unlock

3. Memory and pointers

   After Machine code — test out to unlock

   Trace pointer arithmetic and a buffer on the stack vs heap, and spot a use-after-free or overflow.

   Test out to unlock

4. Processes

   After Memory and pointers — test out to unlock

   Explain fork/exec/wait and file descriptors enough to predict what a small snippet prints.

   Test out to unlock

5. Virtual memory

   After Processes — test out to unlock

   Walk an address through page tables at a toy size, and say what a page fault is doing.

   Test out to unlock

6. Concurrency

   After Virtual memory — test out to unlock

   Spot a race on shared memory, and use a lock or atomic so a counter stays correct.

   Test out to unlock

Why a path, not a playlist

Bits, machine code, memory, processes, concurrency. Later headings open after the one before.

Each heading is its own course with a tutor. Later headings open when you finish — or test out of — the one before.

After you sign in

• •You land on this map — every heading is already there.
• •Take the open class, or test out of a later heading to unlock it.
• •Each heading is one shared course — same syllabus and first class for everyone. Later classes continue on your copy.