this is what
most people would
consider to be "
normal"
text.
Consecutive lines of
text have the least amount of
space between them allowed for
readability.
When people write huge blocks of single spaced text (in email, on everything, or in a long document), it can be difficult to read. Solutions to this include manually placing a lot of blank lines throughout the text (such as the blank line between the previous block of text and this one), double spacing, and probably more techniques that I can't think of right now.