Recruiters for tech position generate leads from various sources like Linked In, GitHub, Stack Overflow, etc. If you're in a software engineering position, it's

Recruiters for tech position generate leads from various sources like Linked In, GitHub, Stack Overflow, etc. If you're in a software engineering position, it's common for recruiters to contact you. If you don't want to switch jobs right now, just reply to the recruiters that contact you and say "I'm happy with my current position." or something similar--short, to the point, professional, not dismissive. The recruiter will keep your email in the system and follow up later. (Sometimes they'll follow up immediately, you can safely ignore immediate followups without explanation.) You can also follow up later and say that you're now interested. You should also know the difference between internal and external recruiters. Internal recruiters tend to be easier to work with just because their incentives are more likely to be aligned with the company that they are hiring with--so if you have some recruiter emails saved in your inbox, start by contacting internal recruiters for companies that you would consider working for.