Addressable strip allows many different lighting effects, each chip being controlled with a microcontroller reading data on the data line.
Current Types available are:
WS2811: Voltage of this strip is 12V, is relatively inexpensive, compatible with most libraries, and resistant to voltage drop. However control is for groups of 3 LEDs instead of individual LEDs. Also 12V means a separate PSU if you’re using it in a 5V environment.
Note: there is a 5V version of the WS2811 available. However this product is in a different price bracket.
WS2812B: Voltage of this strip is 5V, is relatively inexpensive, compatible with most libraries. However power insertion required at least every 5m to keep colour accuracy.
There are a number of other types theoretically available (import) such as WS2812B, WS2813, WS2815, SK9822 and SK6812 all with their own particular advantages etc but have found the above two types appear to address most requirements.
Price is usually listed per meter. Should a specific number of meters be required then please call for a specific quote as the price is may change for above 50 meters!