Sauroposeidon
The press release in 1999 immediately garnered international media attention, which led to many (inaccurate) news reports of "the largest dinosaur ever!". While "Sauroposeidon" likely represents the tallest known dinosaur taxon, it does not hold records for either the longest or most massive. "Patagotitan" or "Argentinosaurus" make better candidates for the title "World's Largest Dinosaur" (presuming to ignore, as is conventional, "Amphicoelias"), though incomplete fossil evidence makes exact rankings impossible.
Evolution of dinosaurs
The sauropods are famous for being the largest land animals that ever lived, and for having relatively small skulls. The enlargement of prosauropod and sauropod dinosaurs into these giants and the change in skull length is illustrated in the following charts.