# Erlang
## Identification
A concurrent functional programming language whose modules commonly use `.erl` and shared headers `.hrl`.
## Notebook evidence
- [[Scanned_20260730-1946|Scanned_20260730-1946]], PDF page 20.
## Relationships and evidentiary boundary
[[Software Supply-Chain Provenance]] · [[Interoperability]].
The notebook occurrence preserves a historical compatibility or software clue. It does not alone prove installation, use, ownership, provenance, or the exact identification of uncertain handwriting.