Two related things, and English lets them share one word. First, the job: the act of putting tiles on a surface — 'the tiling took two days', 'he does tiling and plastering'. Second, the result: the tiled surface itself, all the tiles together as one thing — 'the tiling in the old bathroom is cracked'. That second use is uncountable, which surprises students: you say 'the tiling is cracked', not 'the tilings are'. If you want to count, count tiles: 'three tiles are cracked'. Where you would say 磁磚 in Chinese for both the individual piece and the whole surface, English splits them — 'tile' for the piece, 'tiling' for the whole covered surface treated as one. There is also a maths and design use: a tiling is a pattern of shapes that fits together with no gaps and no overlaps, covering a flat surface forever. That is where you meet phrases like 'a tiling of the plane' or the famous Penrose tiling. Same idea underneath — pieces fitted edge to edge.