You can use native JS so you don't have to rely on external libraries.
(I will use some ES2015 syntax, a.k.a ES6, modern javascript) What is ES2015?
fetch('/api/rest/abc')
.then(response => response.json())
.then(data => {
// Do what you want with your data
});
You can also capture errors if any:
fetch('/api/rest/abc')
.then(response => response.json())
.then(data => {
// Do what you want with your data
})
.catch(err => {
console.error('An error ocurred', err);
});
By default it uses GET and you don't have to specify headers, but you can do all that if you want. For further reference: Fetch API reference