leaflet map reference code example
Example: How to create a leaflet map in javascript
var map = L.map('map').setView([51.505, -0.09], 13);
L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
attribution: '© <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
}).addTo(map);
L.marker([51.5, -0.09]).addTo(map)
.bindPopup('A pretty CSS3 popup.<br> Easily customizable.')
.openPopup();