A great way to break your web traffic without even noticing is through robots.txt. Indeed, the robots.txt file has long been debated among webmasters and it can be a strong tool when it is well written. Yet, the same robots.txt can really be a tool you can shoot yourself in the foot with. We’ve written an in-depth article on the critical mistakes that can ruin your traffic in another post. 
Let’s say you wish to block all URLs that have the PDF. extension. If you write in your robots.txt a line that looks like this: User-agent: Googlebot Disallow: /*.pdf$. The sign “$” from the end basically tells bots that only URLs ending in PDF shouldn’t be crawled while any other URL containing “PDF” should be. I know it might sound complicated, yet the moral of this story is that a simple misused symbol can break your marketing strategy along with your organic traffic. Below you can find a list with the correct robotx.txt wildcard matches and, as long as you keep count of it, you should be on the safe side of website’s traffic.
This is the number of views that you can test each month on your website.It's up to you how you choose to use them, either by allocating all the views to one test or to multiple test, either on one page or on multiple pages. If you have selected the 10.000 tested views plan and you run an experiment on your category page which is viewed 7000 times per month, then at the end of the month 7000 is what you'll be counted as tested views quota.