This part is very interesting because it is able to hold a lot of electronical components, it can be used for prototypes for electronical circuits and be reused for future projects. This can be powered by a female power jack connector.
A basic ultrasonic sensor consists of one or more ultrasonic transmitters (basically speakers), a receiver, and a control circuit. The transmitters emit a high frequency ultrasonic sound, which bounce off any nearby solid objects. Some of that ultrasonic noise is reflected and detected by the receiver on the sensor
PIR Motion Alarms allow you to sense motion, almost always used to detect whether a human has moved in or out of the sensors range. They are small, inexpensive, low-power, easy to use and don't wear out
The Sense HAT, which is a fundamental part of the Astro Pi mission, allows your Raspberry Pi to sense the world around it. In this project, you will learn how to control the Sense HAT's LED matrix and collect sensor data, and you will combine these ideas in a number of small projects.