Page views or unique visitors - which one should you focus on? It depends on your objectives and audience. Let’s start with the basics.
A page view is triggered when any page is loaded by any visitor to your site. For example, if you click this link and the page loads, you have triggered a page view. If you click the link 20 more times today, it will count as 20 page views.
A unique visitor is an individual user who has accessed your site. It is determined by the IP address of the computer or device that the user is browsing from, combined with a cookie on the browser they are using. No matter of how many visits a visitor makes, if he is on the same device and same browser, only one unique visitor is counted. For example, if you visit this link once today, you will be counted as a unique visitor. If you come back to this site 20 more times today, you are still counted as one unique visitor. If you visit the site from another computer or device (or another browser) it will count as a new visitor.
Page views are important for publishers because each page view tally's an ad impression for each ad on the page. If your ads are sold on a cost per thousand views or CPM basis, this is an important number for you to grow. It's tempting to make sacrifices to the user experience to artificially increase page views. For example, an image gallery that loads each new image seamlessly provides a better experience for the user, but will cut down on page views. It's important to find a balance so you don't alienate your audience.
The unique visitors metric gives you a sense of the size of your audience. The relative importance of this depends on the purpose of your site or publication. If you are a brand, you may want to maximize the number of people that come to your site, with little regard for how many pages they access, as long as they follow your chosen path through the site. If you are a niche publisher, you may not have a huge audience, but they may show loyalty and engagement by clicking deep into the site and generating page views.
At the end of the day, the most important factor for growing your page views and unique visitors is content. If your content is not engaging and relevant to your users, they are going to "bounce" and never come back. The "bounce rate" is the percentage of visitors who come to your site and leave within a few seconds. A high bounce rate indicates that visitors didn't like what they saw or didn't find what they were looking for.
The amount of time spent on the page indicates whether users are actually reading or watching what you're serving up. The higher the average time on a page, the more engaged your audience is in that particular page. As a publisher, Increasing this metric provides leverage to increase your ad rates because the ad impression time is longer.