farther, further

Farther and further can both describe a greater distance. A familiar style preference uses farther for physical distance and further for an idea, a degree, or something additional. That distinction can help, but it is not a universal rule.

Distance: We walked farther along the beach.

More discussion: Let’s talk about the idea further.

Additional: Do you have any further questions?

Further is also established for physical distance, particularly in British English: We walked further along the beach. Use further for the everyday meaning additional and for the verb meaning help something progress, as in further an idea. Let your meaning and variety of English guide the choice.