A filet is one of the four health-oriented consumables in the game. Each filet restores 3 hearts of health. A filet is the third most powerful of the four possible health-restoring consumables. For information on the other consumables, see jerky, power jerky, or power filet.
How to Obtain
You can only get filets by either looting them or by killing an armadillo or skunk with a steam cannon. You can also trade for them in a market world.
How to Use
Filets can be used as an ingredient in crafting power filets, or they can be consumed directly to restore health.
There are a couple ways to consume a filet. You can hit F to bring up the Power-Ups panel and then click on the filet icon. You can also put filets into your hotbar, in which case you need to select it, then click anywhere on the screen to consume it. With the hotbar method, it is possible to consume a filet even if your health isn't low enough to make use of the full number of hearts it gives.
Using the Z key will automatically use the most powerful consumable possible, depending on how low your health is.
Also, as of January 2016, on v3 (the only version for PC users), the F key does NOT yet bring up the Power-Ups panel.