I am an IT pro in systems administration and networking and I can tell you that it all has to do with the browser and the tracking cookies. Google Chrome, while being a fantastic browser, allows absolutely the MOST tracking cookies with websites. What this means is that your traffic is being cached and monitored and then displays ads based on what you frequently browse. There are obviously ways around this but as some have mentioned here (I only read the first two posts) is for you to delete your history and cookies, and install an AdBlocker extension for the browser you are using. On iOS/Android there are apps which perform this same function. Good luck!