# The halo2 Book [halo2](README.md) - [Concepts](concepts.md) - [Proof systems](concepts/proofs.md) - [PLONKish Arithmetization](concepts/arithmetization.md) - [Chips](concepts/chips.md) - [Gadgets](concepts/gadgets.md) - [User Documentation](user.md) - [Developer tools](user/dev-tools.md) - [A simple example](user/simple-example.md) - [Lookup tables](user/lookup-tables.md) - [Gadgets](user/gadgets.md) - [Tips and tricks](user/tips-and-tricks.md) - [Design](design.md) - [Proving system](design/proving-system.md) - [Lookup argument](design/proving-system/lookup.md) - [Permutation argument](design/proving-system/permutation.md) - [Circuit commitments](design/proving-system/circuit-commitments.md) - [Vanishing argument](design/proving-system/vanishing.md) - [Multipoint opening argument](design/proving-system/multipoint-opening.md) - [Inner product argument](design/proving-system/inner-product.md) - [Comparison to other work](design/proving-system/comparison.md) - [Implementation](design/implementation.md) - [Proofs](design/implementation/proofs.md) - [Fields](design/implementation/fields.md) - [Gadgets](design/gadgets.md) - [SHA-256](design/gadgets/sha256.md) - [16-bit table chip](design/gadgets/sha256/table16.md) - [Background Material](background.md) - [Fields](background/fields.md) - [Polynomials](background/polynomials.md) - [Cryptographic groups](background/groups.md) - [Elliptic curves](background/curves.md) - [Polynomial commitment using inner product argument](background/pc-ipa.md) - [Recursion](background/recursion.md)