Hi there, glad the post helped! resteem allows you to share steem posts that you like to the people that are following you. It will appear on their feed. It's kind of like sharing a link on your facebool wall to all your friends, it helps give visibility to the author of the post. It doesn't cost you anything to resteem an article, but it can get pretty annoying for your followers if you start spamming them with resteemed posts
The steem FAQ, which I highly recommend that you read, describes resteeming here : https://steemit.com/faq.html#What_is_Resteeming
Okay thank you! Do you need to ask permission to restem someone's post? Sorry if I'm bombarding you with questions, still learning :).
no, you don't, it can't affect them negatively :)