On French T.V. for about 3 minutes in the evening there is a mini-programme called Fallait le savoir (You just had to know). In this programme, two children explain useful information to each other about things like recycling and global warming. It seems to me, though, that the attitude of "il fallait le savoir" applies to many other things in French life as well as environmental awareness.
When I first got my car back in the summer, I decided to do the responsible thing and spent several hours on the internet practising the Code de la Route (Highway Code). As well as (beginning to) get to grips with priorité à droite (the complicated rule by which cars joining a main road from a side street have priority... but only on some roads ... and not on dual carriageways ...unless it's the Paris Périphérique ... and so on) and speed limits in kilometres per hour, I learned a lot about road signs.
Six months down the line, I wonder why I bothered. Because it seems to me that a lot of the time, the information that you need to know isn't actually displayed. For example, if you're driving along a main road in the country at 90 km/h and you have to slow down to 50 km/h to pass through a village, don't expect there to be a sign on the other side of the village telling you that you are now out of the 50 zone and can drive at 90 again. You're just supposed to know.
Likewise with parking. Parking spaces where I live are incredibly expensive to rent, so I park my car in the street wherever I can find a parking place. Back before Christmas, I parked on a wide street with no yellow lines, along with several other cars. Coming back a week later, I scraped the snow off the windscreen to discover a parking ticket under the wiper. After scrutinising the ticket for several days, I was finally able to discover what I had done wrong. My town has alternate parking, where you park on one side of the street for half the month, then switch sides. The switch happens at 8am on the middle day. Which is fine, if inconvenient. Except that today, with the snow gone and time on my hands, I parked in the same street (on the other side) then walked the whole length of the road. A road sign does exist in France to say that alternate parking applies. It's in the Code de la Route. It was not displayed anywhere on that street. The authorities clearly did not feel it was their responsibility to tell me where I could and could not park. Il fallait le savoir.
On the upside, even at a rate of 11 euros a week, paying the parking fines is still cheaper than renting a space!