In renormalization group (RG) flow, the low energy states form a code subspace that is protected against the local short-distance errors. we will discuss the similarities and differences between this approximate error correction code and the classical and quantum codes that appear in the degenerate vacua of local many-body quantum systems. We will consider continuous MERA as a concrete example and discuss how well the low-energy operators are protected. We will argue that at large N and large gap the approximate error correction code becomes exact.