Turtle
Turtles are essentially robots, and were added in the 1.3 update. They run an OS (like the Computers) named TurtleOS. They have the ability to place blocks, break blocks, move around, detect blocks, and drop items in their inventory. The programs they run are stored on floppy disks.
If you would like to know more about how to program them, have a look at the Turtle API.
Floppy Disks
Turtles do not have a built-in floppy drive. As such they need a floppy drive placed next to them to access disks.
Fuel
Turtles have been equipped with a state of the art quantum ionizing engine. This means that, once given fuel (the redstone used to craft them), they do not need to be re-charged, nor do any fuel cells need to be replaced, likewise they don't need to have external power directed to them either.
Crafting
To craft a Turtle:
File:Turtle-craft.png
To craft a Mining Turtle:
File:Turtle-craft2.png
To craft a Wireless Turtle:
File:Turtle-craft3.png
To craft a Wireless Mining Turtle:
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