64 LEDs are used.

Arduino based controller.

Multiplexing techniques to control multiple LEDs with fewer pins.

PWM signals are used  for brightness, and managing arrays and loops for LED states and animations. 

Follow the black and white line.

3 IR sensors for line detection (self made).

Can solve the maze with symbols like (plus, minus, T, --,  etc).

PWM signals are used to control the speed and direction of motors. 

Can work both in water and land.

DPDT switches are used to control the motion.

A computer SMPS power supply is used to power up the robot.

Can perform some specific task as assigned.