As Roy Walker used to say on the TV series Catchphrase, ‘just say what you see’. While there are likely to be some road sign symbols that will bamboozle you, most of the pictures used on signs are straightforward to figure out. For example:
Symbols depicting people usually indicate some kind of pedestrian nearby (children, the elderly, horse riders). Symbols with numbers on their own are usually to do with speed, either to tell you the speed limit or to impose a minimum speed on that road. Numbers that appear alongside other symbols are usually used for clarification, like junction numbers or the maximum height of a vehicle. Symbols with arrows tend to refer to traffic and how it should flow, for example, whether oncoming traffic has priority, or that you cannot make a U-turn.
However, you will come across some signs that make no logical sense, such as a diagonal slash to indicate that the national speed limit applies. In these cases, this is where knowing your specific road signs is essential.