When using a web browser, like Safari, it saves some information from its website to its cache and cookies. Clearing the cache can fix certain issues like long load times and formatting issues.
Clearing cache and cookies will remove settings that were previously in place. For example, if you were signed in to some websites, you will be required to sign back in on your next visit.
Safari:
Open the Safari web browser.
In the upper left-hand corner, click the Safari drop-down button.
Select the time frame to be All Time
Click Clear History
Close all tabs
Try accessing the website again
In general, you should notice an improvement in website load times and web browser performance.
Additional Info
Cookies are files that are created after visiting websites. They are designed to better your online experiences by saving browsing data, and decreasing the amount of time it takes to load the pages in the future.
Caches are what remember certain elements of the pages you visit, for example, images, and help with the total amount of time it takes to reload these images on your next visit.