What Is Website Propagation Or DNS Resolution?

We all use websites everyday, but very few people understand how the internet actually works when it comes to website servers, domain registrars, internet service providers, and web browsers.
Let’s start from the top: Let’s assume we want to launch a new website, what exactly is involved and how does it work?
First we need to sign up with a hosting company and register our domain.  The hosting company is where all your website files are stored to display your website, and the registration company is where you register your .COM domain name to allow people to find your website.  Once you get these things setup, here’s how the process works:
You type in a website, such as www.SimpleSEOGroup.com into a web browser.  This corresponds with an IP address for your website server.  Your request is sent from your computer to your router to your modem to your internet service provider.  Once your internet service provider receives your request, they look up where the request should go by viewing the name servers with your domain registrar.  For example, SimpleSEOGroup.com might correspond with nameserver2200.hostname.com — this directs the request to the proper server at the hosting company.  From here, your website is found on the server and displayed to the end user.  You can actually trace the path from your computer to your website by doing the following:
-On Windows, Start, Run, CMD — then once in the command prompt type in tracert www.websitename.com and you’ll see these results:
This doesn’t mean much to the average internet user, but for someone troubleshooting your website it means a lot as they can find errors between your computer and a set web server.
Let’s get on to the main topic here — website propagation.  When you update your name servers with your domain registrar, it takes time for them to send out this information to the various internet service providers.  What this means is when you build a new website or transfer from one server to another, it takes anywhere from 4 hours up to 48 hours for your new web server to display your website when you type in your domain name.  This DNS resolution wait time can be annoying for website owners, so the best thing to do is change your server late in the evening so any lapse or down time occurs overnight.  In most cases, it takes less than 8 hours for name servers to fully update, but if you have a global website it truly can take up to 48 hours and even longer in some cases.  This is extremely important to keep in mind whenever you’re changing web servers, name registrars, or designing a new website.