Why it is important
A websites navigation is akin to a books index. It is used by users of your site to quickly find the information relevant to them. Many visitors to your site will quickly mouse over the navigation to display the drop downs to see what a site has to offer and then zero in on what they need by clicking on the relevant navigation link.
Main navigation links
The main navigation links are the menu names you can see when you fist open a website. They are generally displayed across the page at the top of a website. A few sites will display them down the left-hand side but this is less common.
The main navigation names may be link directly to a page on the website or have drop down menu items listed under them. If there are drop down menu items under a main navigation item then they should directly relate to the main name. For example if there was a menu item called About Us then suitable drop down names would include; Company Profile, Our Team, Testimonials etc. It is important you get this right as you want to make it as easy as possible for users to navigate around your site. Remember when someone lands on your site you only have a few seconds for them to find what they are looking for or they could well leave.
Google and website navigation
Google also uses a website’s navigation to help index it. Looking at a site’s navigation structure is one-way Google indexes a site so it needs to be logical.
Website navigation should also be text based and not images. Google can read text but not images so if a site’s navigation is displayed in images Google can’t read it so it is a barrier to Google indexing. Some web developers use images as they feel it looks better. You can tell if your website’s navigation is in text by running your mouse over it. If each letter highlights separately then it is text based but if the name highlights as a block then it is an image.
Side bar verses top bar navigation
Should you have the navigation of your site run across the top of the site or down the left-hand side?
Most sites have the navigation run across the page at the top of the site so this is a good reason to follow suit. You want to make it as easy as possible for site visitors to use your website so doing what is most common in this sense seems like a good idea.
If the navigation is displayed down the left-hand side it reduces the width of the space available to display the content on the website making the page longer increasing the need for the user to scroll down.
One caveat to add to the argument for a top bar navigation is that the navigation should be sticky. That means when a user scrolls down a page in the website beyond the bottom of the information displayed at the bottom of the screen, the navigation stays at the top of the screen and the content scrolls up behind it.