What is the difference between regression and smoke testing?

Question

Accepted Answer

**Regression** — retest after changes. **Smoke** — basic functionality check.

**Regression Testing:**
- Re-run existing tests.
- After code changes.
- Ensure no new bugs.
- Comprehensive.

```
Regression:
Code changed → Run all tests
Ensure existing features still work
(Catch new bugs)
```

**Smoke Testing:**
- Basic functionality check.
- Quick sanity check.
- After deployment.
- Limited scope.

```
Smoke Test:
After deploy:
- Can I login?
- Can I see dashboard?
- Can I make a request?
(Basic checks)
```

**Key differences:**
- **Regression** — comprehensive.
- **Smoke** — basic.
- **Regression** — after changes.
- **Smoke** — after deployment.

Systems Analyst: What is the difference between regression and smoke testing?