Is a gift card for an online course a good Christmas present?

I wouldn't just blindly give someone a random course without knowing what they're interested in - that kind of thing just ends up in a drawer. But if you know that someone specifically wants to learn something, whether it's programming, languages, or something creative, a voucher like that is actually perfect because it lets them decide when and how they want to start. The only catch is that a lot of people don't actually finish these courses, so it would make sense to check beforehand whether the person really wants to do self-directed learning.

A gift certificate for an online course can work, but only if you really know the person and know what they're genuinely passionate about. Otherwise it actually ends up in a drawer - I know plenty of people who got something like that as a gift and just never did it because it wasn't what they wanted at the time.

The best thing is if you ask them beforehand or at least observe what's currently fascinating them. Whether it's about crafts, languages, design or whatever - the gift certificate should match a real interest, not some vague hope that they "might eventually" want to learn something. If you're unsure, you can always go with something tangible instead, something you can actually hold. But if you know for a fact "oh, they told me recently that they finally want to learn XY," then the gift certificate is perfect and will actually get used.