Amplifier modules, also known as amplifier boards, are PCB (printed circuit board) modules featuring an audio amplifier chip.
Amplifier modules are pre-assembled boards which can be integrated easily, without the need for soldering the IC. They often contain other components which work alongside the amplifier too. Therefore they are closer to a plug-and-play option.
Modules are sometimes used in prototyping audio amplifier IC designs. Amplifier kits are sometimes interchangeable so you can experiment with different parameters.
Amplifiers, also known as amps, are electronic components which boost an electric current within a circuit. They are used to increase or amplify a signal input which is louder or of a higher quality.
When looking at modules, it is important to consider the input signal and the output signal power you wish to achieve from your amplifier. This is often measured in voltage.