The dynamically generated Values in a script during the test run can be captured using
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Variable
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Constant
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Parameter
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Correlation
Correlation is the technique used to capture dynamically generated server values (like session IDs, timestamps, or transaction IDs) and reuse them later in the script. Without correlation, scripts would fail because the recorded values become invalid. Parameters store static or user-defined data, variables hold temporary values, and constants are unchangeable - none of these capture dynamic server responses.
In load-testing tools like LoadRunner, values generated dynamically by the server at runtime (session IDs, tokens, timestamps, auto-increment keys) change on every recording/run and would break script replay if hardcoded. Correlation is the technique for capturing such a value the moment it's returned during the run and substituting it wherever it's needed later in the script. Variables, constants, and parameters instead handle externally supplied or user-driven data, not values that only exist because the server generated them during that specific run — so Correlation is correct.