The Silk Touch enchantment in Minecraft allows you to mine the blocks and get their drop directly (a diamant ore instead of a diamond block for example). Thanks to this enchantment, you can also recover fragile and brittle objects like glass or ice.
Silk Touch Enchantment Details
You can add the Silk Touch enchantment to any pickaxe, shovel, axe, or shears using an anvil, enchantment table, or command.
The maximum level for the Silk Touch enchantment is level 1. This means that you can only enchant an item with a maximum of Silk Touch I, and nothing more for that enchantment.
Silk Touch Enchantment Incompatibility
If commands are used to apply both Silk Touch and Fortune to an item, the Silk Touch enchantment takes precedence over the Fortune enchantment for blocks affected by both enchantments.
Silk Touch is also [JE only] technically incompatible with the Looting and Luck Of The Sea enchantments. Since Silk Touch cannot normally be applied to swords or rods, it only affects enchanted books and the use of anvils in Creative mode.
If commands are used to apply both Silk Touch and Looting or Luck Of The Sea to an item, both enchantments work normally.