Why is there is $1 charge from you when I add my credit card?
The $1 charge is a temporary pre-authorization from your credit card company, which allows the merchant (DataCamp) to charge your card for the full amount when your final purchase is made.
By pre-authorizing your account, they will not have to place a larger hold on your account. That $1 doesn’t ever come out of your pocket.
If you notice that the $1 does not automatically disappear from your account, or you see the $1 charge showing up on your final credit card statement, you will want to contact your bank. You are also welcome to email email@example.com with additional context.