Start with bits.
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The same literal example, quickstart and support boundaries in eight languages. Detailed guides and interactive controls currently use English.

Learning path

1. 01

   Separate notation from a byte

   10111000 is eight text characters representing one byte, B8. A packer converts notation into byte values. It does not choose an instruction.

   Read: canonical binary source →Inspect: the actual boot source →
2. 02

   Read an opcode and immediate

   In 16-bit mode, B8 2A 00 loads 42 into AX. Change one low opcode bit to choose another register; change an immediate bit to choose another value.

   Try: one-instruction playground →Read: instruction encoding →
3. 03

   Give the bytes a boot environment

   Legacy BIOS loads a first sector at physical 0x7C00. Inspect the explicit code, message, padding, and final 55 AA marker. A marker identifies a candidate; it cannot prove correct behavior.

   Try: boot sector builder →Read: the boot sector layout →
4. 04

   Follow state, one instruction at a time

   A register is a current value, a flag records a condition, and IP selects the next instruction. Step through the model to see a branch follow its signed displacement from the end of an instruction.

   Try: visual CPU lab →Read: simulator boundaries →
5. 05

   Ask a real execution environment

   Package literal source, verify sizes and reviewed hashes, then boot a disposable QEMU guest. Linux ELF examples require Linux x86-64; their expected nonzero exit statuses are demonstrations, not generic failures.

   Read: your first program, without an assembler →Read: validation and evidence →
6. 06

   Solve one problem and explain it

   Use a binary challenge to practice the mechanism you just learned. Then inspect an example’s source and byte table before changing it. Correct bytes and a reproducible check matter together.

   Try: binary challenges →Explore: complete examples →