Actually, for this poem, let’s get even more basic. How about "What is the title?" This poem was the first in the book "Spring and All," and the only title Williams gave it was "I" (as in the roman numeral one, not me, myself and… confused yet?) People who needed a way to refer to this poem just called it by its first line: "By the road to the contagious hospital." Pretty simple, right? Hold on. As the poem became more popular, it got pulled out of the book it was published in, and started to be printed as a stand-alone poem. In some cases, the book’s title was slapped onto the poem. Check out the link above to poets.org. They call this poem "Spring and All."
Poetry purists would definitely get their undies in a bunch over this. To some, changing the poet’s work like this is a big mistake. Maybe (probably?) this change doesn’t bug you in quite the same way, and we’re not here to try and convince you that it’s a big deal. But… (you knew there was a ‘but’) it does make a difference.
Think of the title as a sign that’s planted at the beginning of a trail. The memory of that sign will affect your whole trip. If the sign says "This way to the hospital," it’ll put you in a different frame of mind than if the sign says: "This way to spring, green grass, flowers, etc." If the poem is called "Spring and All," then we may not be so surprised when spring finally appears in the middle. If the poem has no title except the first line, maybe the appearance of spring will feel like more of a change.
In the summary for line 1 (above), we talked about how the contagious hospital looms over the poem, so maybe we have a sense of how it works as a title. But, how about the other possibility? The "Spring" part makes a lot of sense, but how about the "and All?" If we look at it from one side, these two words provide the little bit of mystery and extra complication that Williams loves. His poems focus on basic ideas and simple images, but they approach them in a way that forces you to think a little more about their meaning. Adding the "and All" gives your imagination some space to play, to think of new and different possibilities.