Username vs display name
Understand which identity field must be unique and which one your audience sees.
| Question | Username | display name |
|---|---|---|
| Uniqueness | Username is usually unique | Display name is often reusable |
| Profile URL | Often controls it | Usually does not change it |
| Best use | Stable identity and mentions | Readable brand or personal name |
Bottom line
Check and protect the username because it commonly controls mentions and URLs; use the display name for readable branding.