Many of us grew up with relatively small, low-resolution televisions as the primary — perhaps the only — screen in the home. We didn’t think about it at the time, but these displays had a resolution of roughly 480i. That’s the number of horizontal lines that are drawn across the screen. The “i” means “interlaced”: only half of those lines are changed at a time.

Back in the day, that was the best we had. As screens started getting bigger, the lines became more obvious — and the picture got worse. The industry has standardized on two primary television resolutions: 720 and 1080.

While the TV resolution battles were being fought, something interesting happened: screens became smaller and ended up in our pockets. Let’s take a look at HD screens and see how they’ll influence smartphones, tablets, and TVs.

0:22 History: television resolutions

1:45 What is “interlacing”?

2:30 Technical limitations of broadcast TV

4:37 Big-screen TVs

5:20 What is “High Definition”?

6:40 How does this apply to smartphones and Tablets

8:28 Pros and Cons of HD screens

15:00 Predictions

16:25 Your turn!