Basic design principles

I think the general principle of web page design is to make the web page easy to read.
Three of the four basic design principles, alignment, proximity and contrast, are dealing with how to make the web page easy to read.
Among the three, I think the most difficult one is alignment. It is easily to say that choose one alignment and use it on the entire page. In fact, it is difficult to line everything up, especially for beginners with no background in design. People are so familiar with the appearance of newspaper that they use it as the template to design the web page. That is why people are very likely to center the headline, but align the basic text on the left.
The fourth principle, repetition, is a powerful usability principle that can make users of the web page feel in control of the system. When things always behave the same, users don't have to worry about what will happen. Instead, they know what will happen based on earlier experience. The more users' expectations prove right, the more they will feel in control of the system and the more they will like it.