isDisplayed() vs isVisible() in Selenium

As explained in this post How does Selenium WebDriver's isDisplayed() method work

WebDriver has its own W3C specification. and the section about determining visibility can give you more information from the spec.

Selenium RC - isVisible() - looks for display: none style tag - this might throw a null pointer if we aren't careful...thus to see if an element is visible first check if the element is present using isElementPresent() method. Then try checking if the element is visible! Refer Difference between isElementPresent and isVisible in Selenium RC

Short answer is that isVisible is method of old Selenium RC and isDisplayed is method of Selenium 2.

If you are talking about WebDrivers WebElement, it contains only isDisplayed() method, which by the doc:

Is this element displayed or not? This method avoids the problem of having to parse an element's "style" attribute.

Before webdriver we had Selenium RC, which is now long deprecated, the DefaultSelenium class had isVisible() method that:

Determines if the specified element is visible. An element can be rendered invisible by setting the CSS "visibility" property to "hidden", or the "display" property to "none", either for the element itself or one if its ancestors. This method will fail if the element is not present.

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