The same concept also applies to energy systems. For example, the first steam engines were manufactured using hydro mechanical power (water mills), but once steam engines were used to generate the mechanical power used to manufacture other steam engines, steam power became self hosting.
If a system is so new that no software has been written for it, then software is developed on another self-hosting system and placed on a storage device that the new system can read. Development continues this way until the new system can reliably host its own development. Development of the Linux operating system, for example, was initially hosted on a Minix system. Writing new software development tools "from the metal" (that is, without using another host system) is rare and in many cases impossible.
Several programming languages are self-hosting, in the sense that a compiler for the language, written in the same language, is available. The first compiler for a new programming language can be written in another language (in rare cases, machine language) or produced using bootstrapping. Self-hosting languages include Perl, Lisp, Forth, Pascal, Delphi, C, Modula-2, Oberon, Smalltalk, OCaml, FASM, and FreeBASIC.
The first self-hosting compiler (excluding assemblers) was written for Lisp by Hart and Levin at MIT in 1962. Because Lisp interpreters existed previously, but no Lisp compilers, they used an original method to compile their compiler. The compiler, like any other Lisp program, could be run in a Lisp interpreter. So they simply ran the compiler in the interpreter, giving it its own source code to compile.