"An anti-pattern is a bad design that is worthy of documenting. Examples of anti-patterns in Javascript are the following.
- Polluting the global namespace by defining a large number of variables in the global context.
- Passing strings rather than functions to either setTimeout or setInterval, as this triggers the use of eval() internally.
- Modifying the Object class prototype (this is a particularly bad anti-pattern)
- Using Javascript in an inline form as this is inflexible.
Knowledge of anti-patterns is critical for success. Once we are able to recognize such anti-patterns, we're able to refactor our code to negate them so that the overall quality of our solutions improves instantly."