WordPress is the most popular way to design websites. That’s for a number of reasons: it’s well supported, the main program is free and it’s extremely flexible.
The fact that it’s free software does worry some people but there are lots of reasons why that shouldn’t be something to worry about. Including the fact that the “wisdom of crowds” comes into play keeping the code as secure as possible. Whereas with computer operating systems, we’re at the mercy of companies like Microsoft and Apple to keep on top of those kind of issues.
The problem with free software – or indeed almost any software nowadays – is that we tend to assume that we should be able to work it immediately.
To an extent that’s true with WordPress.