• Statically Typed Languages - each variable and expression is defined at compile time
• Dynamically Typed languages - each variable and expression is defined at run time

Notes

• What could be a squiggly line in the IDE becomes a JIRA ticket reported by an angry customer
• It’s just you delegate writing and executing the test to the compiler
• If restrictions make your code simpler, great! But if restrictions force you to write more complicated code, perhaps the restrictions are wrong