Transformer is normally considered as a wire wound device for transforming from one voltage to another voltage or a current to a voltage, or to isolate so it uses a completely different earth system, in the main with lighting it transforms from 230 volt to 12 volt, except for air craft ground lights which have a special arrangement to ensure all lights are the same light output.
The electronic transformer is a device which was used to replace the transformer, it transforms AC to DC then back to AC at a high frequency, this allows a much smaller wire wound transformer to be used to get voltage required, and the output is monitored and the mark/space ratio changed as it turns DC to AC to correct output voltage, and in some cases also includes an under and over current shut down, it was designed for the quartz lights, so the bulb had a thicker filament and a more accurate voltage which extended the bulb life, the disadvantage is it can shut down with under current.
The driver is the name given to a current controlled device, again air craft ground lights used this current to voltage control to ensure all at the same output, but in domestic it refers to the DC device used to power LED lamps which are current dependent, it is often built into the bulb, and can be a simple resistor or capacitor, or a pulse width modulated device, bulbs with the latter often have a huge voltage range like 10 to 30 volt, it can also be outside the bulb package, typically rated at the mA rating of the LED so 340 mA and has a wide voltage range typically 5 to 60 volt. However the name seems to be given to simple DC power supplies as well, so one needs to be very careful. In the main external drivers are DC, internal drivers built into the bulb can be AC and the frequency of the AC is important I have seen LED bulbs marked 50 Hz so one assumes it has an AC driver (current limiting device) built in. With a true driver you use current limit to suit LED so if LED is 220 mA using a 340 mA driver would damage the bulb.
With an incorrectly named driver where it has a fixed voltage then the amps can be over the LED rating.
With a length of many LED's in a strip the power supply needs to match the lights, I have just bought two Lidi 2 meter lengths of LED lighting, in the package there is a link to link two together, however the strip can use 22 watt and the power supply is rated only just big enough to power one strip, so in real terms should not be linked. The strip can use 2 to 22 watt, it has three different LED's in the strip, one low colour temperature, (reddish) one high colour temperature (very white) and one colour changing likely actually three LED's in the same chip giving green, blue and red with user control. So it has around 6 wires within the strip going into the controller, which is zigbee controlled, and it would be very hard to find a replacement power supply/driver for this set up other than the one which came with the coil of LED's. So although there may be a connector so the unit comes in two or three bits, in real terms this just makes it easier to arrange the lights, they are really one unit.
Often LED's are arranged in the strip as three LED's and a resistor, a white LED will have around 3 volt across it, it is the current not voltage which is important, but if you have three LED's and a resistor in series the resistor is the driver which limits current stopping thermal run away, so the package of the 4 components will run on 12 volt, it will be noted with 12 volt LED lamps often they have multiple of 3 LED's, 3, 6, 9, 12 etc.
The problem is the resistor produces no light just heat, so although a LED will produce around 100 lumen per watt, in some cases up to 120 lumen per watt, in a package with resistors the total can be down to 75 lumen per watt due to the resistor. In fact some even lower than tungsten bulbs, so one has to be careful as some strip lights are only for decoration they don't give off much light.
I would say if the light does not say how many lumen it is decoration only, however those Lidi strips at maximum output have a higher output to my main lights, so in some cases strips of LED can be used for general lighting.
Lighting is not easy, as looking at spread of light as well as lumen output, and the designer of this house seems to have been living in cloud cuckoo land, a bath room which is quite a small room really has two pendent lights, but living room quite large had one, and even with an eight bulb chandelier it does not really light the room, so display cupboard lights are used to supplement the main light, but house before this one the display was decoration only.
So the Ikea strip lights are low output and decoration, the Lidi strip lights help light the room. Yet to look at the Ikea 1 meter strip lights compared with Lidi 2 meter flexible strip until turned on one would expect the reverse. good job the Lidi ones can be turned down, as for display 2 watt is ample, really don't need the 22 watt most of the time.
