Metadata Coverage Page
Do you struggle to memorize all the metadata names?
You can use Metadata Coverage, to find the exact API name of components you are trying to work with (link also in description): https://developer.salesforce.com/docs/metadata-coverage/60
If so, you probably see a similar message:
bash
js@os ~/project (main)> sf project retrieve start --metadata AuraComponentBundle:SuperSecretComponent
Preparing retrieve request... Error
Error (1): The specified metadata type is unsupported: [AuraComponentBundle]Don’t worry, there is a page that can help you!
You can use Metadata Coverage, to find the exact API name of components you are trying to work with (link also in description): https://developer.salesforce.com/docs/metadata-coverage/60

Now I know that the correct name is “AuraDefinitionBundle”:
bash
js@os ~/project (main) > sf project retrieve start --metadata AuraDefinitionBundle:SuperSecretComponent
Retrieving v59.0 metadata from jan@beyondthecloud.sandbox using the v60.0 SOAP API
Preparing retrieve request... Succeeded
Retrieved Source
=================================================================================================
| State Name Type Path
|------------------------------------------------------------------------------------------------
| Changed SuperSecretComponent AuraDefinitionBundle force-app/main/default/aura/SuperSecretComponent/SuperSecretComponent.cmp
| Changed SuperSecretComponent AuraDefinitionBundle force-app/main/default/aura/SuperSecretComponent/SuperSecretComponent.cmp-meta.xml
| Changed SuperSecretComponent AuraDefinitionBundle force-app/main/default/aura/SuperSecretComponent/SuperSecretComponentController.js

