What can I say? In Europe, all cooks measure dry ingredients by weight, not volume (i.e. cups). And I live in France so I have been measuring my ingredients using metric units for over a decade. Hence all recipes here use European standards for measurement; weights are in grams or kilos, volumes are in litres, centilitres, or millilitres, and oven temperatures are in celsius.
To be honest, often exact measurements are not that important; I never weigh ingredients for a stew for example! The only time they are really important is in baking, and even since buying a set of cup measures, I have had endless problems trying to use recipes that measure butter, flour etc. in cups. So the first time I do one of these recipes, I weigh the results and convert the recipe to metric. For the record, one American cup measure equals 220 ml.
If you have arrived here from a place where measurements are done in cups, I urge you to buy a cheap set of scales; if you do a lot of baking, you will find them well worthwhile, as in my experience it makes it so much easier to achieve reliable, reproducible results. In the meantime, I can recommend Diana’s Desserts for a set of conversion tables for common ingredients; I still find it invaluable.
For oven temperatures, you can roughly double the Celsius number to arrive at the Fahrenheit equivalent; again, it is rarely critical. Or use this converter.
When cooking a main course, e.g. stew, one is creating art. On the other hand, baking [with all its interactive ingredients] is a series of chemistry [with, perhaps, a foray into physics] experiments; thus, one needs precision, in order to replicate the results.