> For the complete documentation index, see [llms.txt](https://emca.emudhra.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://emca.emudhra.com/previous-release-versions/v4.2.5/user-manual/ca-administrator/application-settings/certificate-features.md).
# Certificate Features
Different certificate types, such as x509, EMV, and CVC, are available on the emCA platform.
When you first set up emCA, you have the option to choose the certificate features that suit your needs. You can add more features later by selecting "Manage certificate features" and using the edit option if you only selected one feature during the initial setup. If you have already selected all three characteristics, you won't be able to modify them after the initial setup.
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