Codes are vector spaces over finite fields with combinatorial properties, used in Information transmission since 1948, since their inception by Claude Shannon.

Lattices are discrete additive subgroups of the Euclidean space with metric properties studied by classical mathematicians like Gauss, Jacobi, Minkowski. They play an important role today in post quantum crypto.

We survey analogies between these two objects: distance vs minimum, weight enumerators vs theta series, invariant of finite groups vs modular forms.

A direct connection is Construction A which attachs a lattice to a binary code. A variation thereof, Construction B allows for a combinatorial proof of the Jacobi identity.

An abstract version is the Brou\'e -Enguehard map which is a correspondence between polynomial invariants and modular forms.