Predatory conferences
A serious conference can help your research reach a wider audience and raise your profile. A predatory conference can have the opposite effect.
Check carefully whether the organiser is reputable before accepting to attend a conference.
KTH does not have lists of reputable organisers, but there are ways to determine whether the organiser is reputable.
What are ‘predatory’ conferences and how can I avoid them? (AuthorAID)
Predatory publishing: Predatory conferences (NTU, Singapore)