1. busybox --help

BusyBox v1.00 (2005.05.11-02:27+0000) multi-call binary

Usage: busybox [function] [arguments]...

   or: [function] [arguments]...

        BusyBox is a multi-call binary that combines many common Unix
        utilities into a single executable.  Most people will create a
        link to busybox for each function they wish to use, and BusyBox
        will act like whatever it was invoked as.

Currently defined functions:

        [, ar, ash, awk, basename, bunzip2, busybox, bzcat, cat, chgrp,
        chmod, chown, chroot, chvt, clear, cp, cut, date, dc, dd, deallocvt,
        df, dirname, dmesg, du, dumpkmap, echo, egrep, env, expr, false,
        fbset, fdisk, fgrep, free, getkey, grep, gunzip, gzip, head, hexdump,
        hostname, hwclock, id, ifconfig, ifdown, ifup, insmod, ip, kill,
        killall, klogd, ln, loadfont, loadkmap, logger, logname, logread,
        losetup, ls, lsmod, md5sum, mkdir, mkfifo, mknod, mkswap, mktemp,
        modprobe, more, mount, mv, nc, netstat, nslookup, od, openvt,
        pidof, ping, ping6, pivot_root, printf, ps, pwd, readlink, renice,
        reset, rm, rmdir, rmmod, route, run-parts, sed, seq, sh, sleep,
        sort, start-stop-daemon, strings, stty, swapoff, swapon, sync,
        syslogd, tail, tar, tee, telnet, test, tftp, time, top, touch,
        tr, traceroute, true, tty, udhcpc, umount, uname, uniq, unzip,
        uptime, vi, watch, wc, wget, which, who, whoami, xargs, yes, zcat