Understanding Cron Expressions
Cron expressions are string patterns that tell systems exactly when to run automated tasks — from Unix cron jobs to Azure Functions, AWS Lambda, Google Cloud Scheduler, and CI/CD pipelines. This article explains what cron is versus a cron expression, breaks down the five standard fields (minute, hour, day of month, month, day of week), covers Quartz's seconds and year extensions, walks through special characters like *, /, -, ?, L, and #, and includes a practical reference table of common schedules with real-world examples.