Check out example codes for "font roboto css". It will help you in understanding the concepts better.

Code Example 1

@import url('https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,500,500i,700,700i,900,900i');

Code Example 2

@font-face {
    font-family: 'Roboto';
    src: url('Roboto-ThinItalic-webfont.eot');
    src: url('Roboto-ThinItalic-webfont.eot?#iefix') format('embedded-opentype'),
         url('Roboto-ThinItalic-webfont.woff') format('woff'),
         url('Roboto-ThinItalic-webfont.ttf') format('truetype'),
         url('Roboto-ThinItalic-webfont.svg#RobotoThinItalic') format('svg'); (under the Apache Software License). 
    font-weight: 200;
    font-style: italic;
}

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