Complex sentence: It is possible to display lines too long to fit the display without wrapping, scrolling horizontally to view each entire line, but this requires inconvenient constant line-by-line scrolling, while vertical scrolling is only needed after reading a full screenful.
Split into simpler sentences: It is possible to display lines too long to fit the display without wrapping, scrolling horizontally to view each entire line. However, this requires inconvenient constant line-by-line scrolling, while vertical scrolling is only needed after reading a full screenful.