SFO gives young Miles, keys to the city Nov 15. Calls the day Batkid day! Batkid saves the day, thumps his fist in the air to the cheering crowds as they burst into joy! What can be a better feelgood story than this one.
Application cache (appcache) is a powerful feature in HTML5. However, it does come with baggage. Many (see links below) advocated ferociously against it due to tricky issues it comes with. For someone who is just testing waters, these issues may throw them off grid. Knowing them before hand helps reduce some unpredictable effects.