In one sentence, describe what the following article is about:

Tap the Settings app icon, which resembles a set of gears on a grey background. This option is around a third of the way down the Settings page. It's about halfway down the page. The switch will turn white {"smallUrl":"https:\/\/www.wikihow.com\/images\/2\/25\/Iphoneswitchofficon.png","bigUrl":"\/images\/thumb\/2\/25\/Iphoneswitchofficon.png\/47px-Iphoneswitchofficon.png","smallWidth":460,"smallHeight":294,"bigWidth":"47","bigHeight":"30","licensing":"<div class=\"mw-parser-output\"><p>I edited this screenshot of an iPhone icon\n<\/p><p>License: <a rel=\"nofollow\" class=\"external text\" href=\"http:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a><br>\n<\/p><\/div>"}, signifying that your iPhone's Safari browser will now allow cookies. If the "Block All Cookies" switch is white, your iPhone's Safari browser is already enabling cookies.

Summary:
Open your iPhone's  Settings. Scroll down and tap Safari. Scroll down to the "PRIVACY & SECURITY" heading. Tap the green "Block All Cookies" switch .