The problem with sliders is that although they're cute, small and snack-size, if they're good (and there's no point in eating them if they're not), it's hard to stop at just one.
Many people would describe sliders as "mini hamburgers" and that's what the word was originally limited to - the White Castle hamburger chain in the United States is widely credited with creating them. But the meaning of the word has expanded to encompass many other ingredients that are sandwiched between the two halves of a small hamburger bun; I've tasted a buffalo chicken slider (good, although it would have been better made with chicken thigh, rather than the breast), salmon cake slider (not so good) and a pulled pork slider (delicious).
The best sliders I've ever eaten were at l'Atelier de Joel Robuchon, in The Landmark, Central. They harked back to the original in that they were hamburgers, but they were taken way, way up to another level: the burgers were made from Kagoshima beef and, as if that were not indulgent enough, each one came with a small, thick slab of seared foie gras.