LFS is about building a Linux distribution from scratch (i.e. using the Linux kernel.)

The book in question is about how to build your own operating system (i.e. a non-Linux) kernel from scratch.

> We'll implement basic context switching, paging, user mode, a command-line shell, a disk device driver, and file read/write operations in C. Sounds like a lot, however, it's only 1,000 lines of code!