No problem, we all learn it quickly enough here. For example, TDP is just a maximum heat dissipation number that is only loosely correlated with power consumption and PSU wattage is a combined number for all rails, making it nearly useless these days because only one type of rail matters anymore and that's the +12V rail (or rails, for those PSUs that have more than one).
TDP is also calculated differently on different models (IE some card's TDPs may be closer to their realistic power consumption than others). For example, a Radeon 7970 may have a TDP of 250W and a GTX 680 a TDP of 195W, but their power consumption is still much closer because the 680 uses very nearly its TDP in gaming workloads, yet the 7970 usually doesn't get anywhere near its TDP in gaming workloads. Other examples of TDP not working with power consumption well is how AMD's 250W TDP Radeon 6970 uses less power than Nvidia's 244W TDP GTX 580.
PSU wattage is even worse because it can have different meanings for the PSU. For example, some may have their rating be their maximum short-term wattage whereas others may have it be their maximum recommended 24/7 wattage. Even worse, some PSU companies blatantly lie about their PSU wattage on some models...
Ehh, sorry if I'm ranting on and on.