If you use the recommended Iron Router, you use the go
method:
Router.go('/articles/example');
or:
Router.go('showArticle', {name: 'example'});
If you use the old Router, use:
Meteor.Router.to('/articles/example');
If you don't use any router, start right now. In the meantime, use the stone-age method:
window.location.href = '...';