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## Expressions

An expression is data that has a certain structure. For example, credit card numbers typically have 16 digits and appear in the format "nnnn-nnnn-nnnn-nnnn", making them suitable for expression-based detections.
You can use predefined and customized expressions. For details, see Predefined Expressions and Customized Expressions.
Related information

- Predefined Expressions
- Customized Expressions
- Adding and Editing Expressions
- Importing Expressions