Canon EOS 4000D Instruction Manual page 53

Format the card in the following cases:
The card is new.

The card was formatted by a different camera or a computer.

The card is full with images or data.

A card-related error is displayed (p.294).

Low-level Formatting
Perform low-level formatting if the card's recording or reading speed seems

slow or if you want to totally erase data on the card.
Since low-level formatting will format all recordable sectors on the card, the

formatting will take slightly longer than normal formatting.
You can stop the low-level formatting by selecting [Cancel]. Even in this

case, normal formatting will already be complete and you can use the card
as usual.
When the card is formatted or data is erased, only the file management
information is changed. The actual data is not completely erased. Be aware
of this when selling or discarding the card. When discarding the card,
execute low-level formatting or destroy the card physically to prevent the
personal data from being leaked.
The card capacity displayed on the card format screen may be smaller

than the capacity indicated on the card.
This device incorporates exFAT technology licensed from Microsoft.

3 Formatting the Card
53