According to Wikipedia: A shell is a user interface for access to an operating system's services.
Bash is a command line (CLI) unix shell. It stands for the Bourne again shell.
There are many shells out there, from the Bourne shell (sh), to more modern shells like zsh and fish. I personally recommend Zsh.
Open up your favorite terminal emulator :)
Open up your Terminal.
For better features and a more powerful terminal, install iTerm2.
You will also want Homebrew for package management.
You could use bash for Windows 10.
Developing on a Windows computer is needlessly complicated, so I would recommend either dualbooting or running some flavor of Linux in a VM. VMWare is free for UIUC students on the webstore and VirtualBox is free.
ls - List Directory Contents
cd <dir> - Change Directory
pwd - Print Working Directory
mkdir <dir> - Make a directory
touch <file> - Make a file
nano - Basic text editor
cat <file> - "Concatenates" files to standard output (the terminal output)
cp <file> <dest> - Copy a file
mv <file> <dest> - Move a file
rm <file> - Remove a file
man <command> - Information about commands
Commands will often let you specify flags, or additional options to them in the format -<char>.
Here are some interesting flags that may be useful:
ls -a - List all (including hidden files)
ls -l - List files in long form
ls -la - List all files in long form
rm -r - Remove recursively
sl -alFc - ?????
With the command line, there must be a way of installing new programs. This is where package management comes in. Package management programs allow you to install and delete programs. These programs vary depending on what type of system you have.
Debian based Linux - Apt
MacOS - Brew
You can install python from your package manager. Be careful you install the correct version as there are differences between python 2 and python 3
python <pythonfile.py> - Run a python program
python --version - Check your python version
You can install java from your package manager. Just like python there are many different java versions so be careful.
javac <javafile> - Compile a Java program
java <javaprogram> - Run your java program
You can redirect a program's standard out into another program's standard in with the pipe character.
fortune | cowsay - ?????