Arduino shields are boards that will expand the functionalities of your Arduino. You just need to plug them over the top of the Arduino board. There are countless types of shields to do countless tasks.
Here’s a collection of 25 Arduino Shields.
I’ve also wrote a list of 21 modules that you can buy for your Arduino for less than $2.
1. Ethernet Shield
The Ethernet Shield allows you to connect your Arduino to the internet . You just have to plug the shield onto the Arduino board and then, connect it to your network. Pretty simple.
2. Relay Shield
The Relay Shield is a module with 4 mechanical relays that provides you an easy way to control high voltage.
The ProtoShield is a prototyping Shield that makes it easy to prototype. It allows for easy connections between the breadboard and the Arduino.
4. Motor Shield
This Shield allows an easy control of motor direction and speed. It makes it easy to incorporate a motor into any of your projects.
5. LCD Shield
This Shield makes it easy to use a 16×2 Character LCD. With this, it is possible to control a 16×2 Character LCD, up to 3 backlight pins and 5 keypad pins using only the two I2C pins on the Arduino.
6. Capacitive Touchpad Shield
The Touchpad Shield allows you to build simple capacitive touch interfaces.
7. CAN-BUS shield
The CAN–BUS Shield adopts MCP2515 CAN buscontroller with SPI interface and MCP2551CAN transceiver to give CAN–BUS capibility to the Arduino.
8. Smoke Detector Shield
This Shield can detect concentrations of combustible gas in the air and read it as an analogue value. Useful to make a smoke detector system.
9. Negative Voltage Generation Shield
This shield generates negative voltage for Arduino. It is useful if you need negative voltage.