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##### 14.8.2.11 `:cache`

The `:cache` header argument controls the use of in-buffer caching of the results of evaluating code blocks. It can be used to avoid re-evaluating unchanged code blocks. This header argument can have one of two values: `yes` or `no`.

- `no` The default. No caching takes place, and the code block will be evaluated every time it is called.
- `yes` Every time the code block is run a SHA1 hash of the code and arguments passed to the block will be generated. This hash is packed into the `#+results:` line and will be checked on subsequent executions of the code block. If the code block has not changed since the last time it was evaluated, it will not be re-evaluated.