In essence, the Imp provides an easy, integrated way to connect almost any hardware device both to other devices and to internet services. It's more than just a WiFi card, or even a WiFi module with processing built in - it's an integrated platform that deals with the drudgery of connectivity, allowing you to concentrate on the application instead of the mechanics.
The Imp itself is very small - 32mm x 24mm x 2.1mm - but packs a lot inside.
For starters, there's industry standard 802.11b/g/n WiFi, complete with WEP, WPA and WPA2 encryption, along with a great antenna.
Next, there's the processor. A Cortex-M3 core gives great performance combined with low power consumption, allowing the Imp to deal with both maintaining a secure connection to the service and also executing the developer's code in a stable environment.
Finally, there's the I/O. Though there are only six pins available for application use, they're six very capable pins. UARTs, I2C, SPI, analog in and out, PWMs, GPIOs... all selectable under software control.
The Leaf Maple is a microcontroller board based on the STM32F103RB
microprocessor. The Maple runs at a maximum of 72 MHz, has 39 digital
input/output pins, 16 analog inputs, native full speed USB, 3 USARTs
(hardware serial ports), integrated SPI/I2C support, a power jack, and a
reset button. Maple is programmable over USB via our provided DFU
bootloader, no extra hardware required! Users can also program the
onboard program flash via external JTAG interface. Maple offers security
support for read/write protected addresses, as well as User and Handler
processor modes. It has a real-time sysTick, useful for a real time OS
or any timing senstitive applications. 6 advanced interrupt timers will
help you here as well. Maple can be powered via USB, a wall adapter, or
it can run off of a rechargeable lipo battery (see below for more info).
The Maple is compatible with shields designed for the Arduino
Duemilanove or Diecimila.