Manioc starch is made from the yucca plant, which grows in tropical areas of Africa, Asia and the Americas. It's used as a thickener in cooking and is sometimes used as a binder in baking, especially vegan baking. In the U.S., it's more commonly known as tapioca starch or cassava starch. There are several ingredients that you can substitute for manioc starch in a recipe.
You can use cornflour in place of manioc starch in a recipe. In baked goods, you replace any manioc starch with the exact same amount of cornflour. If using to thicken a fluid-based recipe -- such as a soup, sauce or stew -- 1 tbsp, dissolved in a slurry with 1 tbsp cold water, thickens 1 cup of liquid. Note that cornflour is harder to dissolve, freezes less nicely and works poorly with acidic ingredients in comparison with manioc starch.
Arrowroot starch is used in baking and added to liquids in order to thicken them in same way as cornflour. Like manioc starch, arrowroot starch freezes well. It has a neutral taste, so it works well in subtly flavoured dishes. However, it's not advisable to use this ingredient to thicken dairy-based recipes, as it will make them have a slimy texture.
ClearJel is a product made from modified cornflour, and is often used by commercial bakers. Its main use is to thicken pie fillings. Although it can be used as a general thickener, it would work out much more expensive than other options. The original ClearJel product breaks down when frozen, but you can use it if you're canning or jarring your pie fillings. Instant ClearJel freezes well, but you shouldn't use it if you're canning or jarring your filling.
Potato starch is gluten-free and it's also suitable for use during Passover, unlike other thickeners made from grains. It's normally used to thicken soup, gravy and other savoury recipes by making a slurry and adding it. But it can also be used in baked goods. Potato starch doesn't freeze well. Don't boil a liquid that has potato starch in it, as it will ruin the consistency.