Website usability is not about finding information for your product or services, it is the ease in which your visitors can navigate as easy as possible.
Readers do not read websites, they scan, meaning that you have only a few seconds to convince them that they are in the right place indeed to find what they are searching for.
Usable and readable website content is a combination of efforts between web designers and web content writers. Web pages must be designed to facilitate the ease of reading content through the effective use of colours, typography and spacing. Simultaneously the content writer must enable readers to quickly identify, read and process the information.
Bear in mind these 3 key factors regarding website usability.
First of all, number one:
Text and typography have to be legible, smooth and pleasant to read.
Content should be easy to understand, never use jargon.
Finally, number three:
Content should be skimmable because as mentioned in the very beginning, the visitors of your websites do not read, they scan.
Below you will find an excellent infographic from Quicksprout on how to improve website usability and keep all the visitors happy.