By using electronic bricks, you may connect Arduino compatible boards easily with various digital, analog and I2C/Uart interfaces. These the breadboard-less firm connection are prepared to extensive modules like poteniometers, sensors, relays, servos...even buttons, just plug and play. 

Each terminal module has buckled port with VCC, GND and Output, which has corresponding port on the sensing board, with a plain 2.54mm dual-female cable you may start playing already. Buckled brick cables are like cement for bricks, make the connections easier, secure and more professional looking.

Sitting on a seeeduino