(Why) Some HTML is "optional"

Chris Coyier blogged recently on weird looking HTML. It's a nice short post and I'd say it's worth knowing these optional features (potentially known as defaults). My favourite optional is <script> and not having to include the type attribute. But Chris' first example is the most common, the optional closing </p> tag. What (I think) is an interesting question is: why? READER DISCOUNTSave $50 on te

[ginpei]

<P>の閉じタグを省略できる理由。原初HTMLでは段落を括るのではなく段落間の区切りとして実装されていた。