If you don't need as much computing power as the Arduino Uno Rev3 or the Mega 2560 Rev3, then the Arduino Micro is for you. It is one of the smallest boards in the Arduino family.
The Arduino® Micro is one of the smallest boards in the Arduino family, yet it is still powerful. No need to worry about soldering on male headers because they come preinstalled.
ATmega32U4 Microcontroller Specs:
20 digital I/O pins (7 can be used as PWM output and 12 as analog input)
Clocked at 16 MHz
32KB of flash memory
2.5KB of SRAM
1KB of EEPROM
5Vdc operating voltage
Peripherals:
Micro USB receptacle to power and program Micro
Reset button
ICSP header
Need more digital and analog I/O than the Uno can provide? Upgrade to the Arduino® Mega 2560 Rev3!, ATmega2560 Microcontroller Specs:, 54 digital
Arduino Mega 2560 Rev3
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Need more digital and analog I/O than the Uno can provide? Upgrade to the Arduino® Mega 2560 Rev3!, ATmega2560 Microcontroller Specs:, 54 digital
Arduino Mega 2560 Rev3
Arduino Uno Rev3 Quick Start Guide
Arduino Uno Rev3 — Arduino Official Store, uno
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