1.0shabeeb Bloghttp://shabeebk.com/blogshabeebhttp://shabeebk.com/blog/author/admin/rich600338<blockquote class="wp-embedded-content" data-secret="Ag2WuHXJUs"><a href="http://shabeebk.com/blog/promises-and-call-back/">promises and call back</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="http://shabeebk.com/blog/promises-and-call-back/embed/#?secret=Ag2WuHXJUs" width="600" height="338" title="“promises and call back” — shabeeb Blog" data-secret="Ag2WuHXJUs" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script type="text/javascript"> /*! This file is auto-generated */ !function(d,l){"use strict";var e=!1,o=!1;if(l.querySelector)if(d.addEventListener)e=!0;if(d.wp=d.wp||{},!d.wp.receiveEmbedMessage)if(d.wp.receiveEmbedMessage=function(e){var t=e.data;if(t)if(t.secret||t.message||t.value)if(!/[^a-zA-Z0-9]/.test(t.secret)){for(var r,a,i,s=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),n=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),o=new RegExp("^https?:$","i"),c=0;c<n.length;c++)n[c].style.display="none";for(c=0;c<s.length;c++)if(r=s[c],e.source===r.contentWindow){if(r.removeAttribute("style"),"height"===t.message){if(1e3<(i=parseInt(t.value,10)))i=1e3;else if(~~i<200)i=200;r.height=i}if("link"===t.message)if(a=l.createElement("a"),i=l.createElement("a"),a.href=r.getAttribute("src"),i.href=t.value,o.test(i.protocol))if(i.host===a.host)if(l.activeElement===r)d.top.location.href=t.value}}},e)d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",t,!1),d.addEventListener("load",t,!1);function t(){if(!o){o=!0;for(var e,t,r,a=-1!==navigator.appVersion.indexOf("MSIE 10"),i=!!navigator.userAgent.match(/Trident.*rv:11\./),s=l.querySelectorAll("iframe.wp-embedded-content"),n=0;n<s.length;n++){if(!(r=(t=s[n]).getAttribute("data-secret")))r=Math.random().toString(36).substr(2,10),t.src+="#?secret="+r,t.setAttribute("data-secret",r);if(a||i)(e=t.cloneNode(!0)).removeAttribute("security"),t.parentNode.replaceChild(e,t);t.contentWindow.postMessage({message:"ready",secret:r},"*")}}}}(window,document); </script> promises and call back are only doing similar job,  but sometimes we have to think whether to have a callback function or promises. Here we will be discussing about promises and call back function. So let have look on both callback function and promises and how it works. Call back function Callback functions are functions …