PUSH is when an entry is "pushed onto" the stack. POP is when the last pushed entry is "popped off" the stack.

Notepad is one of the simplest text editors available. It is only capable of the most minimal formatting, such as different fonts and sizes. WordPad is similar to Notepad, but gives you more formatting options...

RAM is volatile and used for both read and write. ROM is non-volatile and only used for reading. Memory on the RAM is erased when the computer is switched off.

Hardware is the physical aspect of the computer, the thing we can touch, such as monitor, hard drive, etc. Software is the non-physical aspect which includes the operating system, applications, programs, etc.