#swipebox-slider .slide{--wpr-bg-bc1d7b1b-2c9a-4d26-a53c-ae0f0356f8aa: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/loading.gif');}#swipebox-action #swipebox-prev,#swipebox-action #swipebox-next,#swipebox-action #swipebox-close{--wpr-bg-558a36ec-7260-43fd-9a35-17ea613ade95: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/gallery-controls.png');}.flex-direction-nav a{--wpr-bg-0154aa60-b2ed-49b1-bf08-f4da0d9036fb: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/pixel.gif');}.posts-slider .loading li{--wpr-bg-eb2a3d9c-d186-474f-8f2c-414eb4039b50: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/loading.gif');}.col_1{--wpr-bg-af5b8303-491c-4663-b478-45916be04ded: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/diagonal-tile-gray.png');}#most_recent{--wpr-bg-31f38c33-5c23-4c36-9018-42b8b3da2008: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/cross-hatch.png');}#home_ad{--wpr-bg-1d62ac35-0858-4507-ba67-3cd56db22d44: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/home_ad_bg.jpg');}#homepage_quote{--wpr-bg-c05623ff-be88-461f-9743-f7e15b78cf24: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/quote_bg.jpg');}header#masthead div.search_box{--wpr-bg-3d58d585-c38c-48b2-8700-7328ee4aacf8: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/search_container_bg.png');}.ui-tabs div.ui-tabs-panel{--wpr-bg-cfe590dd-b381-4b48-a1eb-b822be96a9fb: url('https://www.primermagazine.com/wp-content/themes/simplemag/images/tab-bg.jpg');}.rll-youtube-player .play{--wpr-bg-4075c5b2-51cf-4cc8-8927-92d9fb66a8dd: url('https://www.primermagazine.com/wp-content/plugins/wp-rocket/assets/img/youtube.png');}

Know It All

Know It All: Why Do So Many Zippers Bear the Letters ‘YKK’?

Whether you were zipping up your jacket, fly, or duffel bag, you've frequently spotted these three letters and wondered about their meaning. Wonder no more.

Know It All: The First Movie Commercially Released on VHS

Most people seem to know that Twister represented the maiden flight for the now-standard format of DVD, in 1997 (and if you didn’t already know that… well, that’s a freebie on top of this week... [more]