3 typing questiuons (questions for the smartest people here) ;-)?

[Dave]

1. Why is "I" always uppercase? (when alone)

We've all been tought that from elementary school, but is there any real reason? a's are not capitalized by them selves? (unless there the start of a sentence)

2. Why is y sometimes a vowel sometimes not?

3. # hashtags? All these dang foiled kids these days talking about hash tags. What in tar-nations are Hash tags?

thanks
Dave