What is the point of using await in asynchronous methods?

Question

Studying on asynchronous/synchronous operations one point was not clear, which would be the use of the await in methods async as in this example found on MS’s own website. If the method GetGizmosAsync() is declared asynchronous what is the sense of using a await in httpClient.GetAsync(uri) would not be better than GetGizmosAsync() was already declared without the async?

public async Task<List<Gizmo>> GetGizmosAsync()
{
    var uri = Util.getServiceUri("Gizmos");
    using (HttpClient httpClient = new HttpClient())
    {
        var response = await httpClient.GetAsync(uri);
        return (await response.Content.ReadAsAsync<List<Gizmo>>());
    }
}