The L298N Motor Driver is a controller that uses an H-Bridge to easily control motors direction and PWM to control the speed. This module allows you to independently manage two motors of up to 2A each in both directions. Supply range may vary between 5V and 35V, enough for most DC motor projects.
We often use the power supplies like batteries or direct AC/DC supply which are normally in higher ranges compared to the actual requirement for the circuit. In that cases we need this kind of voltage regulators which can regulate and vary the voltage levels for the circuit requirement.
The AMS1117 series of chips are linear voltage regulators with low voltage drop. The modules based on the AMS1117 chip provide constant 3.3V or 5V outputs from an unregulated DC input. It's very compact and can be included in your project schema or you can use it together with a breadboard for circuit testing.