Different Advertisements

Have you ever noticed when you go on websites like Facebook, Twitter, Instagram and other social networks there are advertisements that are related to things you are interested in. Recently, I have noticed this more then normal. Websites I have been on to online shop are showing up under these social networks. If the website has a sale or a new item I instantly know about it because of this. This form of advertisement is different then ones we have done in the past. We are no longer only using commercials and billboards to learn about new items we are interested in. We have these on are pages that are literally focused on our own interests. Do you believe this form of advertisement is better then other forms?