For websites, the term performance refers to the loading speed or the computing power of a server, in other words, the speed at which data is transmitted from server to client.
A website that loads slowly, may encourage potential customers to abort. To ensure smooth interaction, something should be done proactively for good performance. Especially with the increasing use of mobile devices, a positive impression through unobtrusive, fast loading is important to convert visitors to customers. When a page loads slowly, the visitor may bounce and then click the search result of a competitor. The performance of a website has gained in importance because websites are getting larger and the networks are getting slower through higher loads.
Smooth interaction with a website keeps visitors there and creates trust. Simultaneously, operating costs can be reduced. Better performance also means reduced site speed which can have a positive effect on search engine ranking.
There are many ways to improve the performance of websites. There are just a few listed here which can account for a few seconds. Not every method would be advisable for every website, which is why it should always be checked before execution whether or not the effort will pay off.
It is possible, to cache files, i.e. store them in a buffer on the client side. For example, if an image gets stored in the cache upon the first visit to that page, it can be loaded from there for the second visit. The page will load faster because the image does not have to be transferred. Caching is only useful for files that do not change frequently. A corresponding entry must be made in the .htaccess file to get this executed.
Each page element is an HTTP request. A browser can load between two and eight of these elements at the same time, all others go into a kind of queue. Thus, it takes longer to load a page completely, regardless of the available bandwidth.
Another advantage of less requests involves the fact that each file has its own header. It has to be sent with each request and therefore grouping of graphics or CSS files makes sense.
To reduce the overall data quantity to be transmitted, files should be kept small. Increased bandwidth is not an argument, because at the present time visits with mobile devices must be reckoned with.
Cookies also affect the performance. Any cookie and any information in a cookie should only exist if it is useful. For example, the collection and transmission of data which will actually not be used can be dispensed with.
Small improvements can also be made to CSS stylesheets. The reason is that CSS selectors have different processing times. Highly suitable are ID (#) and class (.). However, the wildcard selector (*) and the descendant selector (>) are slower. Another small factor is the @import command, which may block further loading in some browsers until the imported file itself is loaded.
Site speed is a confirmed ranking factor and therefore performance is essential from an SEO perspective. Moreover, visitors quickly leave pages that load slowly. It can come down to milliseconds. Large websites have often tested the impact of performance on customer behavior. Amazon, for example, intentionally delayed the loading time of the product pages by 100ms. As a result, sales decreased by one percent.
In a study by Yahoo, loading of the homepage was delayed by up to 400ms, with the result that nine percent of visitors closed the page before loading was completed. The shopping search engine Shopzilla cut its loading time by 3.5 seconds through performance optimization. Revenues increased subsequently by twelve percent. The optimization of performance therefore happens as part of search engine optimization. For comparison, it would be advisable, to evaluate competitor websites with the appropriate tools as well. Google Insights is one tool that can be utilized. A URL which is being tested with regard to site speed can be specified. The tool will then generate proposals, as to how the loading speed can be improved.