Dirt Block

Dirt Blocks are one of the most common block types in the game, covering the majority of the world's surface. They are almost surely the most visible and accessible block to new players, making them useful for building a rudimentary shelter to take refuge during the first night. Dirt blocks may be covered by regular grass, corrupted grass, crimson grass, or hallowed grass (upon engaging hardmode), which spreads from nearby grass-covered dirt blocks. It can be moved around freely with a Dirt Rod.

Location
All caves above the elevation of 0 ft are made of dirt. When the Underground starts (<0 ft), the caves are made of roughly 50% dirt. Small patches of dirt can be found in the Underground layer, though it is mostly made of Stone. After the Wall of Flesh has been defeated in a world, new dirt is formed when Mud Blocks are converted by Corruption or Crimson.

Properties
Dirt blocks are one of the most fragile blocks in the game. A single hit from most Pickaxes will successfully mine them, but dirt blocks with any kind of grass on them will take two hits. Dirt below sea level, as well as dirt surrounded by blocks on all 8 sides, serves as a natural barrier for The Corruption, The Crimson, and The Hallow, as it cannot be converted without grass growing on it.

History
Bloc de terre 흙 블록 Dirt Block Земля