#!/bin/bash
# Experiment 1: Demonstrate UNIX directory structure and navigation commands
# Run: chmod +x 01_unix_directory_navigation.sh && ./01_unix_directory_navigation.sh

echo "============================================"
echo " UNIX Directory Structure & Navigation"
echo "============================================"

echo
echo "--- pwd: print working (current) directory ---"
pwd

echo
echo "--- ls: list files in current directory ---"
ls

echo
echo "--- ls -l: long listing with permissions, size, date ---"
ls -l

echo
echo "--- ls -a: include hidden files (starting with .) ---"
ls -a

echo
echo "--- mkdir demo_dir: create a new directory ---"
mkdir -p demo_dir
ls -d demo_dir

echo
echo "--- cd demo_dir: change into demo_dir ---"
cd demo_dir
echo "Now inside: $(pwd)"

echo
echo "--- cd .. : go up one level ---"
cd ..
echo "Now inside: $(pwd)"

echo
echo "--- cd / : go to root directory ---"
cd /
echo "Now inside: $(pwd)"

echo
echo "--- cd ~ : go to home directory ---"
cd ~
echo "Now inside: $(pwd)"

echo
echo "--- tree-like view of a few top-level dirs ---"
ls /
echo
echo "Quick reference:"
echo "  pwd     -> show current dir"
echo "  ls      -> list contents"
echo "  cd dir  -> enter dir"
echo "  cd ..   -> up one level"
echo "  cd /    -> root"
echo "  cd ~    -> home"
echo "  mkdir d -> create directory d"
echo "  rmdir d -> remove EMPTY directory d"