The Uno for Arduino:
It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started.
The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega8U2 programmed as a USB-to-serial converter and has a resistor pulling the 8U2 HWB line to ground, making it easier to put into DFU mode.
The LCD Keypad Shield for Arduino: It includes a 16x2 HD44780 White on Blue LCD module and a 5 push button keypad for menu selection and user interface programming. Fully assembled. On-line Arduino tutorial and example code. Compatible with Arduino Uno, Mega, Duemilanove. Uses digital pins 4 - 10, and analog pin 0.
The XBee board for Arduino: It mates directly with the Arduino USB board and allows to wireless communicate over a modified ZigBee protocol using the popular XBee module from Maxstream.
The Sensor Shield V4.0 for Arduino: allows you to connect to various modules like sensors, servos, relays, buttons, potentiometers.
1 Uno for Arduino
1 LCD Keypad shield
1 XBee Shield
1 Sensor Shield V4.0