Centered text.

Left-aligned text.

Right-aligned text.

This line contains justified text. Since the only way to properly see this effect is to have enough text to cover at least a couple of lines, so this is more wordy than the other examples.

This paragraph is not justified. Notice that the text at the right margin of this paragraph is "ragged" as compared to the previous paragraph, meaning that the words do not fill in all of the space between the left and right margins of the browser window.