Does bash have its own echo, printf, [ functions?
===

when i trace output of the of nice.sh script with strace, i see tons of child processes.

    strace -ff -o nice.o ./nice.sh 

nice.sh

    #!/bin/bash

    while /usr/bin/[ 1 ]
    do
    	echo ..;
    done;

on the other hand if i run the script below, i do not see any forked child process.

    #!/bin/bash

    while [ 1 ]
    do
    	echo ..;
    done;

same is also true for echo, /bin/echo and printf, /usr/bin/printf. Does it mean that for some commands are embedded into bash? If yes, what are the other commands?