"The Apollo 11 mission's computers were less powerful than today's mobile phones."

In 1970, a year after the human race set foot on the moon, Martin Cooper of Motorola conceived the idea of the first handheld mobile phone. Since then, the mobile phone has evolved at a rapid rate, and evidence showed that it's not going to stop any sooner. It's difficult to imagine how we made such an advance in mobile technology in such a short period, and reached a point where today, most of us use mobile devices to complete many activities in our day-to-day life.

I still remember the day I bought my first mobile phone. It didn't have any fancy stuff that you find in today's mobile phones. The only advanced feature that it had was the Short Message Service (SMS). It didn't have a camera, all the applications were pre-installed, the user couldn't install any applications, and there was no Internet browsing.

However, nowadays, we use mobile devices for many things because communication through a mobile device is faster, cheaper, and can connect to anyone from anywhere. According to surveys, the number of active mobile devices and human beings crossed over somewhere around the 7.19 billion mark. It means that each and every person in the world most likely has a mobile device. Because of this large consumer group, many organizations and consumers invested and made their marketing campaigns to cater to mobile users and as a result, each and every day thousands of new mobile applications and mobile websites have been introduced into the market.

However, today mobile applications and mobile websites have a fatal flow. Websites' sizes are getting bigger at an alarming rate, and we are quickly heading towards the wrong way. We never notice it as it happens, and when we do, it's often too late.

I had the privilege to work with excellent internal developers to complete a website a couple of months back, and our initial goal was to build the website in such a manner that it loads at top speed. Although we planned everything upfront to achieve our goal, we made a fundamental mistake. When we saw the designs, it was already approved by the top management and we never saw the designs upfront before they were sent to the client. Then we got the internal deadline defined by the management, and it was too tight. Then, Make it fast turned into Make it work and we thought we can make it faster later; of course that later never came.

After a couple of months' hard work, we managed to launch the website, but it was a disaster. The site looked great in frontend, but it took more than 20 seconds to load the home page. The website was responsive, and when we came into a mobile breakpoint, it loaded a lot of unwanted elements that shouldn't be there. Once we saw this flaw, we had to work very hard even at night to tweak the website, and after a massive effort, we managed to load the website within 7 seconds.

That day we promised ourselves to check and plan everything upfront, and never leave anything behind to damage the site's performance. So, in this book, I am going to discuss a few tips, tricks, and tools that I have learned in the past couple of years. I hope it will help you to improve your website's loading time by at least a couple of seconds.

Remember, many studies and surveys have shown how a website's performance has a direct impact on the user's interaction with the website. I've listed a few of these as follows:

• 4 percent of mobile phone users visiting a mobile site will abandon a site that takes longer than five seconds to load. (Source of this information: https://blog.kissmetrics.com/loading-time/.)
• Every additional second added to the site's load time results in a 7 percent loss in conversions.
• Similarly, shaving two seconds off of Mozilla's landing pages led to a 15.4 percent increase in conversions, which meant 60 million more downloads per year. This is just a two-second difference, so any impact that you can make will have the potential to improve your business. (Source of this information: http://www.yottaa.com/blog/application-optimization/marketing-web-performance-101-how-site-speed-impacts-your-metrics-.)
• 46 percent of the people who abandon their shopping carts cite slow website speeds to be the reason to do so.
• 79 percent of shoppers who are dissatisfied with the website's performance are less likely to buy from the same site again. (Source of this information: http://conversionxl.com/11-low-hanging-fruits-for-increasing-website-speed-and-conversions/.)