Font Awesome.
You can use a set of 400+ icons from Font Awesome
<i class="fa-heart"></i> fa-heartResult: fa-heart

fa-adjust[]

fa-adn[]

fa-align-center[]

fa-align-justify[]

fa-align-left[]

fa-align-right[]

fa-ambulance[]

fa-anchor[]

fa-android[]

fa-angle-double-down[]

fa-angle-double-left[]

fa-angle-double-right[]

fa-angle-double-up[]

fa-angle-down[]

fa-angle-left[]

fa-angle-right[]

fa-angle-up[]

fa-apple[]

fa-archive[]

fa-arrow-circle-down[]

fa-arrow-circle-left[]

fa-arrow-circle-o-down[]

fa-arrow-circle-o-left[]

fa-arrow-circle-o-right[]

fa-arrow-circle-o-up[]

fa-arrow-circle-right[]

fa-arrow-circle-up[]

fa-arrow-down[]

fa-arrow-left[]

fa-arrow-right[]

fa-arrow-up[]

fa-arrows[]

fa-arrows-alt[]

fa-arrows-h[]

fa-arrows-v[]

fa-asterisk[]

fa-automobile(alias)
[]

fa-backward[]

fa-ban[]

fa-bank(alias)
[]

fa-bar-chart-o[]

fa-barcode[]

fa-bars[]

fa-beer[]

fa-behance[]

fa-behance-square[]

fa-bell[]

fa-bell-o[]

fa-bitbucket[]

fa-bitbucket-square[]

fa-bitcoin(alias)
[]

fa-bold[]

fa-bolt[]

fa-bomb[]

fa-book[]

fa-bookmark[]

fa-bookmark-o[]

fa-briefcase[]

fa-btc[]

fa-bug[]

fa-building[]

fa-building-o[]

fa-bullhorn[]

fa-bullseye[]

fa-cab(alias)
[]

fa-calendar[]

fa-calendar-o[]

fa-camera[]

fa-camera-retro[]

fa-car[]

fa-caret-down[]

fa-caret-left[]

fa-caret-right[]

fa-caret-square-o-down[]

fa-caret-square-o-left[]

fa-caret-square-o-right[]

fa-caret-square-o-up[]

fa-caret-up[]

fa-certificate[]

fa-chain(alias)
[]

fa-chain-broken[]

fa-check[]

fa-check-circle[]

fa-check-circle-o[]

fa-check-square[]

fa-check-square-o[]

fa-chevron-circle-down[]

fa-chevron-circle-left[]

fa-chevron-circle-right[]

fa-chevron-circle-up[]

fa-chevron-down[]

fa-chevron-left[]

fa-chevron-right[]

fa-chevron-up[]

fa-child[]

fa-circle[]

fa-circle-o[]

fa-circle-o-notch[]

fa-circle-thin[]

fa-clipboard[]

fa-clock-o[]

fa-cloud[]

fa-cloud-download[]

fa-cloud-upload[]

fa-cny(alias)
[]

fa-code[]

fa-code-fork[]

fa-codepen[]

fa-coffee[]

fa-cog[]

fa-cogs[]

fa-columns[]

fa-comment[]

fa-comment-o[]

fa-comments[]

fa-comments-o[]

fa-compass[]

fa-compress[]

fa-copy(alias)
[]

fa-credit-card[]

fa-crop[]

fa-crosshairs[]

fa-css3[]

fa-cube[]

fa-cubes[]

fa-cut(alias)
[]

fa-cutlery[]

fa-dashboard(alias)
[]

fa-database[]

fa-dedent(alias)
[]

fa-delicious[]

fa-desktop[]

fa-deviantart[]

fa-digg[]

fa-dollar(alias)
[]

fa-dot-circle-o[]

fa-download[]

fa-dribbble[]

fa-dropbox[]

fa-drupal[]

fa-edit(alias)
[]

fa-eject[]

fa-ellipsis-h[]

fa-ellipsis-v[]

fa-empire[]

fa-envelope[]

fa-envelope-o[]

fa-envelope-square[]

fa-eraser[]

fa-eur[]

fa-euro(alias)
[]

fa-exchange[]

fa-exclamation[]

fa-exclamation-circle[]

fa-exclamation-triangle[]

fa-expand[]

fa-external-link[]

fa-external-link-square[]

fa-eye[]

fa-eye-slash[]

fa-facebook[]

fa-facebook-square[]

fa-fast-backward[]

fa-fast-forward[]

fa-fax[]

fa-female[]

fa-fighter-jet[]

fa-file[]

fa-file-archive-o[]

fa-file-audio-o[]

fa-file-code-o[]

fa-file-excel-o[]

fa-file-image-o[]

fa-file-movie-o(alias)
[]

fa-file-o[]

fa-file-pdf-o[]

fa-file-photo-o(alias)
[]

fa-file-picture-o(alias)
[]

fa-file-powerpoint-o[]

fa-file-sound-o(alias)
[]

fa-file-text[]

fa-file-text-o[]

fa-file-video-o[]

fa-file-word-o[]

fa-file-zip-o(alias)
[]

fa-files-o[]

fa-film[]

fa-filter[]

fa-fire[]

fa-fire-extinguisher[]

fa-flag[]

fa-flag-checkered[]

fa-flag-o[]

fa-flash(alias)
[]

fa-flask[]

fa-flickr[]

fa-floppy-o[]

fa-folder[]

fa-folder-o[]

fa-folder-open[]

fa-folder-open-o[]

fa-font[]

fa-forward[]

fa-foursquare[]

fa-frown-o[]

fa-gamepad[]

fa-gavel[]

fa-gbp[]

fa-ge(alias)
[]

fa-gear(alias)
[]

fa-gears(alias)
[]

fa-gift[]

fa-git[]

fa-git-square[]

fa-github[]

fa-github-alt[]

fa-github-square[]

fa-gittip[]

fa-glass[]

fa-globe[]

fa-google[]

fa-google-plus[]

fa-google-plus-square[]

fa-graduation-cap[]

fa-group(alias)
[]

fa-h-square[]

fa-hacker-news[]

fa-hand-o-down[]

fa-hand-o-left[]

fa-hand-o-right[]

fa-hand-o-up[]

fa-hdd-o[]

fa-header[]

fa-headphones[]

fa-heart[]

fa-heart-o[]

fa-history[]

fa-home[]

fa-hospital-o[]

fa-html5[]

fa-image(alias)
[]

fa-inbox[]

fa-indent[]

fa-info[]

fa-info-circle[]

fa-inr[]

fa-instagram[]

fa-institution(alias)
[]

fa-italic[]

fa-joomla[]

fa-jpy[]

fa-jsfiddle[]

fa-key[]

fa-keyboard-o[]

fa-krw[]

fa-language[]

fa-laptop[]

fa-leaf[]

fa-legal(alias)
[]

fa-lemon-o[]

fa-level-down[]

fa-level-up[]

fa-life-bouy(alias)
[]

fa-life-ring[]

fa-life-saver(alias)
[]

fa-lightbulb-o[]

fa-link[]

fa-linkedin[]

fa-linkedin-square[]

fa-linux[]

fa-list[]

fa-list-alt[]

fa-list-ol[]

fa-list-ul[]

fa-location-arrow[]

fa-lock[]

fa-long-arrow-down[]

fa-long-arrow-left[]

fa-long-arrow-right[]

fa-long-arrow-up[]

fa-magic[]

fa-magnet[]

fa-mail-forward(alias)
[]

fa-mail-reply(alias)
[]

fa-mail-reply-all(alias)
[]

fa-male[]

fa-map-marker[]

fa-maxcdn[]

fa-medkit[]

fa-meh-o[]

fa-microphone[]

fa-microphone-slash[]

fa-minus[]

fa-minus-circle[]

fa-minus-square[]

fa-minus-square-o[]

fa-mobile[]

fa-mobile-phone(alias)
[]

fa-money[]

fa-moon-o[]

fa-mortar-board(alias)
[]

fa-music[]

fa-navicon(alias)
[]

fa-openid[]

fa-outdent[]

fa-pagelines[]

fa-paper-plane[]

fa-paper-plane-o[]

fa-paperclip[]

fa-paragraph[]

fa-paste(alias)
[]

fa-pause[]

fa-paw[]

fa-pencil[]

fa-pencil-square[]

fa-pencil-square-o[]

fa-phone[]

fa-phone-square[]

fa-photo(alias)
[]

fa-picture-o[]

fa-pied-piper[]

fa-pied-piper-alt[]

fa-pied-piper-square(alias)
[]

fa-pinterest[]

fa-pinterest-square[]

fa-plane[]

fa-play[]

fa-play-circle[]

fa-play-circle-o[]

fa-plus[]

fa-plus-circle[]

fa-plus-square[]

fa-plus-square-o[]

fa-power-off[]

fa-print[]

fa-puzzle-piece[]

fa-qq[]

fa-qrcode[]

fa-question[]

fa-question-circle[]

fa-quote-left[]

fa-quote-right[]

fa-ra(alias)
[]

fa-random[]

fa-rebel[]

fa-recycle[]

fa-reddit[]

fa-reddit-square[]

fa-refresh[]

fa-renren[]

fa-reorder(alias)
[]

fa-repeat[]

fa-reply[]

fa-reply-all[]

fa-retweet[]

fa-rmb(alias)
[]

fa-road[]

fa-rocket[]

fa-rotate-left(alias)
[]

fa-rotate-right(alias)
[]

fa-rouble(alias)
[]

fa-rss[]

fa-rss-square[]

fa-rub[]

fa-ruble(alias)
[]

fa-rupee(alias)
[]

fa-save(alias)
[]

fa-scissors[]

fa-search[]

fa-search-minus[]

fa-search-plus[]

fa-send(alias)
[]

fa-send-o(alias)
[]

fa-share[]

fa-share-alt[]

fa-share-alt-square[]

fa-share-square[]

fa-share-square-o[]

fa-shield[]

fa-shopping-cart[]

fa-sign-in[]

fa-sign-out[]

fa-signal[]

fa-sitemap[]

fa-skype[]

fa-slack[]

fa-sliders[]

fa-smile-o[]

fa-sort[]

fa-sort-alpha-asc[]

fa-sort-alpha-desc[]

fa-sort-amount-asc[]

fa-sort-amount-desc[]

fa-sort-asc[]

fa-sort-desc[]

fa-sort-down(alias)
[]

fa-sort-numeric-asc[]

fa-sort-numeric-desc[]

fa-sort-up(alias)
[]

fa-soundcloud[]

fa-space-shuttle[]

fa-spinner[]

fa-spoon[]

fa-spotify[]

fa-square[]

fa-square-o[]

fa-stack-exchange[]

fa-stack-overflow[]

fa-star[]

fa-star-half[]

fa-star-half-empty(alias)
[]

fa-star-half-full(alias)
[]

fa-star-half-o[]

fa-star-o[]

fa-steam[]

fa-steam-square[]

fa-step-backward[]

fa-step-forward[]

fa-stethoscope[]

fa-stop[]

fa-strikethrough[]

fa-stumbleupon[]

fa-stumbleupon-circle[]

fa-subscript[]

fa-suitcase[]

fa-sun-o[]

fa-superscript[]

fa-support(alias)
[]

fa-table[]

fa-tablet[]

fa-tachometer[]

fa-tag[]

fa-tags[]

fa-tasks[]

fa-taxi[]

fa-tencent-weibo[]

fa-terminal[]

fa-text-height[]

fa-text-width[]

fa-th[]

fa-th-large[]

fa-th-list[]

fa-thumb-tack[]

fa-thumbs-down[]

fa-thumbs-o-down[]

fa-thumbs-o-up[]

fa-thumbs-up[]

fa-ticket[]

fa-times[]

fa-times-circle[]

fa-times-circle-o[]

fa-tint[]

fa-toggle-down(alias)
[]

fa-toggle-left(alias)
[]

fa-toggle-right(alias)
[]

fa-toggle-up(alias)
[]

fa-trash-o[]

fa-tree[]

fa-trello[]

fa-trophy[]

fa-truck[]

fa-try[]

fa-tumblr[]

fa-tumblr-square[]

fa-turkish-lira(alias)
[]

fa-twitter[]

fa-twitter-square[]

fa-umbrella[]

fa-underline[]

fa-undo[]

fa-university[]

fa-unlink(alias)
[]

fa-unlock[]

fa-unlock-alt[]

fa-unsorted(alias)
[]

fa-upload[]

fa-usd[]

fa-user[]

fa-user-md[]

fa-users[]

fa-video-camera[]

fa-vimeo-square[]

fa-vine[]

fa-vk[]

fa-volume-down[]

fa-volume-off[]

fa-volume-up[]

fa-warning(alias)
[]

fa-wechat(alias)
[]

fa-weibo[]

fa-weixin[]

fa-wheelchair[]

fa-windows[]

fa-won(alias)
[]

fa-wordpress[]

fa-wrench[]

fa-xing[]

fa-xing-square[]

fa-yahoo[]

fa-yen(alias)
[]

fa-youtube[]

fa-youtube-play[]

fa-youtube-square[]
Simple Line Icons.
You can use a set of 162 icons from Simple Line Icons
<span class="icon-heart"></span> icon-heartResult: icon-heart