The PICAXE-14M IC is a tiny single-chip computer that you can program in a graphical flowchart-like language or easy to learn BASIC. This one a good upgrade from the small 08 or 08M models.
In general, the 'PICAXE' system is a powerful, low cost microcontroller programming system designed to simplify educational and hobbyist use of microcontrollers. PICAXE chips can be programmed in a graphical 'flow-chart' environment or in easy to understand BASIC.
Memory (lines)= Approximate number of lines of program code the chip can hold.
Data Memory = Bytes of EEPROM memory on board "128(- Prog)" means 128 Bytes less the space needed for your program. 256+I2C means 256 Bytes + any external EEPROM space you add via the I2C interface).
Polled Interrupt= A process that automatically checks a pin in between each command to see if something has happened (very useful!)