If you are driving to a holiday destination this year then you will most probably use a sat nav or plan your route on a map before you go. Many people use sat navs on their phone rather than buying an often costly separate unit but these sat nav apps are not always quite as sophisticated and if there are closures or traffic on your route you may not be aware of them.
Google maps is a brilliant free satellite navigation system that does factor in traffic and will often offer you alternative routes if it notices there is a quicker one whilst you are driving. What it may not do is pick up when there is a temporary road closure either due to ongoing road works or if an accident has recently happened. For this reason it is always good to have an idea of an alternative route. You should never try and change your sat nav when driving so if you do need to reroute, stop and look at the route, once you have started to drive along it you should find your sat nav will automatically re-route you and you will be back on track heading towards your final destination once again.