The Ultim... — Building Robots With Lego Mindstorms:

: The original programmable brick from the late 90s, which is the focus of older editions of the Ferraris' book. 🏗️ Structural Building Blocks

: Measured by the number of beam holes they span (e.g., 3-length or 5-length axles), these are used to connect wheels and gears. Building Robots With Lego Mindstorms: The Ultim...

: These form the rigid chassis of the robot. Beams in the EV3 kit can be as long as 15 holes. : The original programmable brick from the late

: The predecessor to the EV3, which introduced more advanced sensor and motor connections. Beams in the EV3 kit can be as long as 15 holes

: Various "proper pieces" like touch, light, ultrasonic (for distance), and gyro sensors allow your robot to interact with its environment.

The most critical "proper piece" is the programmable microcomputer that controls your robot's actions. EV3 Intelligent Brick Go to product viewer dialog for this item.

In "Building Robots with LEGO Mindstorms: The Ultimate Guide" by Mario and Giulio Ferrari, a "proper piece" for starting your build often refers to the core structural components or the "brains" of the robot.