I have a 'problem' with the company MEO regarding sites text alignment. He wants that all sites we make to have justied paragraphs. I don't say that i don't like this, but i don't want to justify all sites paragraphs because in my opinion it doesn't look good everywhere, and I also think that it's easier and nicer to read it left aligned. So... I want your opinion... how users prefer to read the paragraphs? left or justified? Give me reasons too if u can/want this.
On one of the projects I was on a while back we had someone request the same thing. We ran a couple usability tests on a sample paragraph and found that the justified text was slightly less readable to users than the text that had been left aligned.
In followup interviews with the test subjects we asked there opinions on the justification of the text. Almost everyone answered that they prefered the left aligned paragraphs to the justified ones.
If everythings justified it's harder for your eye to scan down the page I think. If it's left algigned there's a clearer definition for the starting point of each line.
I agree with the people that stated Left to be optimal. It's probably that a common rule in our writting methods (left aligning of content) keeps our native reading functions bound to it.
However, for people in the arabic world (where right aligning is used) left would be as confusing to them as is right to us. Altough adaptable, the human eye experiences fatigue in time if it is supposed to read something in a non-native way.
Imagine reading a newspaper article written in a graffitti style.
This is down to what are you going to use your aligning for, but if it's used on content and large textual areas, left would be most reccommended in order to keep a reader focused on the subject rather than the positioning of words and phrases.
Justified is better when there are columns of text as the gutters give the eye a rest. For one-column layouts, left is better as others have already stated. The size of the font also has a bearing on the appearance in either case.