This is a memo of the tools that I commonly use but often forget where to find.
Online Compiler and Debugger
GDB online is an online compiler and debugger tool for C, C++, Python, Java, PHP.
Front-End Design and Development
Online CSS/HTML/JS Previewer.
SSH and FTP Tools
Extremely powerful SSH/FTP tool for Windows.
FTP tool for Linux.
Online Book for Bash Users.