zlatkov

// ajax(..) is some arbitrary Ajax function given by a library
var response = ajax('https://example.com/api');

console.log(response);
// `response` won't have the response

zlatkov

ajax('https://example.com/api', function(response) {
    console.log(response); // `response` is now available
});

zlatkov

// ajax(..) is some arbitrary Ajax function given by a library
var response = ajax('https://example.com/api');

console.log(response);
// `response` won't have the response

zlatkov

ajax('https://example.com/api', function(response) {
    console.log(response); // `response` is now available
});

zlatkov

console.log('asda');

zlatkov

// This is assuming that you're using jQuery
jQuery.ajax({
    url: 'https://api.example.com/endpoint',
    success: function(response) {
        // This is your callback.
    },
    async: false // And this is a terrible idea
});

zlatkov

function first() {
    console.log('first');
}
function second() {
    console.log('second');
}
function third() {
    console.log('third');
}
first();

zlatkov

console.log('Hi');
setTimeout(function cb1() { 
    console.log('cb1');
}, 5000);
console.log('Bye');

zlatkov

setTimeout(myCallback, 1000);

zlatkov

console.log('Hi');
setTimeout(function() {
    console.log('callback');
}, 0);
console.log('Bye');