[OFF-TOPIC] It is true that is impossible write in binary code, the lowest level of programming that you can write is in hex code?

[françai s]

I intend to write in lowest level of computer programming as a hobby.

It is true that is impossible write in binary code, the lowest level
of programming that you can write is in hex code?

What is the lowest level of programming computers that you can write ?

Is binary code?

Is hex code?

Is another machine code? Honestly do not know if it is true that there
is another machine code beyond the binary and hex code.

Is Assembly?