JSFiddle - React, Tailwind, and code Playground
HTML
<script src="http://openlayers.org/api/OpenLayers.js"></script>
<div id="map" style="width:500px; height:500px;"></div>
JavaScript
init();
function init(){
//Map
var map = new OpenLayers.Map("map", {
projection: new OpenLayers.Projection("EPSG:900913")
});
//Base Layer
var osm = new OpenLayers.Layer.OSM();
map.addLayer(osm);
//Vector Layer
var vectorLayer = new OpenLayers.Layer.Vector("Simple Geometry", {
projection: new OpenLayers.Projection("EPSG:4326")
});
map.addLayer(vectorLayer);
//Point
var point = new OpenLayers.Geometry.Point(10.08820, 53.5545);
//point.transform(new OpenLayers.Projection("EPSG:4326"), new OpenLayers.Projection("EPSG:900913"));
var pointFeature = new OpenLayers.Feature.Vector(point);
vectorLayer.addFeatures([pointFeature]);
map.zoomToMaxExtent();
}