/fill command

/fill <x1> <y1> <z1> <x2> <y2> <z2> <TileName> [dataValue] [oldBlockHandling] [dataTag]
Fill with replace (simple block data only):
/fill [x] [y] [z] [x] [y] [z] [BlockName] [Data] replace [filterBlockName] [filterData]

► Fill a cubic area with a particular block with optional data values and tags.

/fill -260 68 248 -256 72 252 minecraft:ice 0 replace
/fill -260 68 248 -256 72 252 minecraft:ice 0 destroy
/fill -260 68 248 -256 72 252 minecraft:web 0 keep
/fill -260 68 248 -256 72 252 minecraft:quartz_ore 0 hollow
/fill -260 68 248 -256 72 252 minecraft:redstone_block 0 outline
/fill -260 68 248 -256 72 252 minecraft:air 0 destroy

/fill -260 68 248 -256 80 252 minecraft:chest 0 destroy {Items:[{id:minecraft:diamond_sword,Slot:13,tag:{ench:[{id:16,lvl:5}]}},{id:minecraft:apple,Slot:0},{id:minecraft:apple,Slot:2},{id:minecraft:apple,Slot:6},{id:minecraft:apple,Slot:8},{id:minecraft:apple,Slot:10},{id:minecraft:apple,Slot:16},{id:minecraft:apple,Slot:18},{id:minecraft:apple,Slot:20},{id:minecraft:apple,Slot:24},{id:minecraft:apple,Slot:26}]}

More information:
oldBlockHandling is either 'replace' (block substitution including replacing air blocks), 'destroy' (destroyed blocks drop as entities), 'keep' (only replaces air blocks), 'hollow' (fills outer layer and replaces inner layers with air), or 'outline' (fills outer layer and leaves all inner layers untouched).