If you are creating a website in this day and age then you need to understand that responsive design is vital. If you do not have a responsive web design in place then you are doing yourself a massive disservice. In fact, it is probably going to cost you a nice heap of cash. Let me explain why.
How do you access the internet? I am willing to wager that you use far more than your PC and Laptop to do it. In fact, most people do. Nowadays the vast majority of us have internet access wherever we go. We have it on our smartphones. We have it on our tablet devices, and it is even on our televisions. The internet is everywhere. So, how does this have an impact on web design? Well, every device that you access the internet on has a completely different screen size. What may look fantastic on your PC may look absolutely dire on a cellphone. In fact, it may look so dire that people veer away from looking at it.
This is where responsive web design comes into play. This is a system where the look of the page will be automatically adjusted depending on the device that it is accessed on. Perhaps one of my biggest complaints of ‘old style’ web design is the fact that it is VERY difficult to read text or even navigate around the pages when accessed through a mobile device. Most people are going to be having the same problems as me. In fact, it is so difficult that when I browse a site like this I will instantly disappear because I really don’t want to put too much effort into browsing it (remember, we as humans are inherently lazy in just about everything that we do!)
Responsive web design is something that is going to need to be built into your design from the start. I am sure it is possible to retroactively shape a design into something slightly more responsive. However, if you are putting in that amount of work then you may as well just start from scratch. You will end up with something FAR better as a result.
Now, you may remember that in the past, there were many people out there developing mobile web sites. This was a completely separate website from your normal one. When people accessed your main site it would automatically redirect them. This was good for the time. Technology has moved on from this point though. I would NEVER suggest going down that route again. Perhaps the main reason is the fact that having a separate site means that you have two that need to be updated. This is most likely not something that you want. With a responsive web design you are only going to have to worry about updating one website. This means you will only have to focus on making one site as best as it can be. You will then draw in the customers as a result.
Image Source: https://dribbble.com/pierreborodin