"The Tyger" contains only six stanzas, and each stanza is four lines long. The first and last stanzas are the same, except for one word change: "could" becomes "dare."
"The Tyger" is a poem made of questions. There are no less than thirteen question marks and only one full sentence that ends with a period instead of a question mark. Addressing "The Tyger," the speaker questions it as to its creation – essentially: "Who made you Mr. Tyger?" "How were you made? Where? Why? What was the person or thing like that made you?"
The poem is often interpreted to deal with issues of inspiration, poetry, mystical knowledge, God, and the sublime (big, mysterious, powerful, and sometimes scary. Ever heard the phrase, "To love God is to fear him"? That’s talking about something sublime). But it’s not about any one thing: this is William Blake.
For better or worse, there really is no narrative movement in "The Tyger": nobody really does anything other than the speaker questioning "the Tyger." The first stanza opens the central question: "What immortal hand or eye, / Could frame thy fearful symmetry?" The second stanza questions "the Tyger" about where he was created, the third about how the creator formed him, the fourth about what tools were used. The fifth stanza goes on to ask about how the creator reacted to his creation ("the Tyger") and who exactly was this creator. Finally, the sixth restates the central question while raising the stakes; rather than merely question what/who could create the Tyger, the speaker wonders: who dares.