When my mother taught me to cook, she showed me how to prepare green beans by snapping the ends off each one - a simple but tedious task. When I started cooking on my own, I prepped them more efficiently, by lining them up and slicing off the ends.
However, my mother's method would have averted a problem I encountered recently as I cooked green beans for a dinner party. I had chopped off the ends as usual, but, when I tasted them before serving, I realised they were an old-fashioned 'breed' that still had tough strings running down each side of the pod. This is what gives the vegetable its alternate name of 'string bean'. These strings are removed when the end is snapped off, not cut.
The name is mostly irrelevant now, because many of the cultivars on the market are stringless. Since you can't tell if they have strings just by looking at them, it's a good idea to check. Another name, snap beans, is more appropriate as the vegetable isn't necessarily green - it can also be yellow, purple and other shades. Another reason 'snap bean' works is that it's descriptive: the fresh beans should snap when you break off the ends; if they're too soft and flexible, they're not fresh. Size is frequently an indication of tenderness: slender beans (such as the stringless type known as haricots vert) are more delicate than thicker, fatter snap beans.
For a quick side dish, I often cut green beans into 2cm lengths then stir-fry them with halved garlic cloves and a splash of soy or fish sauce. If I want a more substantial dish, I add minced pork: heat oil in a wok, add the pork and use a spatula to stir-fry the meat until it loses its pink colour. Remove the meat from the wok, add a little more oil then add minced garlic and chopped red bird's-eye chillies. Stir-fry briefly but don't let the garlic brown. Add the string beans (cut into 2cm pieces) and stir, then add a little water to the wok. Stir, cover with the lid and let the string beans cook until they're crisp-tender. Remove the lid, add the pork and season with fish sauce, a little sugar, salt and ground pepper, then simmer for just a few minutes. Remove from the wok and serve with steamed white rice.