One removes the file from your rig, and the other tries to heal the infected data.
Quarantine moves the offending file.
Knowing which action to take in a given situation is crucial to the health of your system.

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What’s the Difference?
Here’s a quick rundown of their functions:
Deletion is tricky.
This could affect the functionality of your operating system and programs.
If it’s a true virus, the best option is to clean.
The best rule of thumb is to proceed along the continuum from the safe option to the safest.
Start by cleaning the virus.