Consider a similar css code:
@font-face {
font-family: 'MyFont';
src: url('../fonts/MyFont.eot');
src: local('Proxima'), url('../fonts/MyFont.woff') format('woff'), url('../fonts/MyFont.ttf') format('truetype'), url('../fonts/MyFont.svg') format('svg');
font-weight: normal;
font-style: normal;
}
Does this code determine more HTTP requests to download all the formats or does the browser choose the best supported format?
Nope, browser will choose one compatible format. Feel free to add as many sources as you like :)