They didn't; it was Dumbledore's plan. Snape agreed to go along.
As for the reasons:
As for the reasons:
As for the reasons:
As for the reasons:
So Harry would not interfere in the plan Snape and Dumbledore had agreed on.
he gives him a container filled with all the important memories of Snape's that he (Snape) thinks will be useful to Harry, or explain things more clearly. They (mostly) revolve around Snape and Lily (Potter's Mum) starting from childhood right up to the time that Lily dies and the discussion that followed (with Dumbledore) after. It explains to Harry that even before Harry came to Hogwart's Snape was trying to help him, acting as spy for Dumbledore. Snape loved Lily so much that he protected her only son by spying even though he could have died because of it. It also explains to Harry that he (Harry) must die at Voldemort's hand to destroy the seventh Horcrux (himself).
Draco was the actual master of the elder wand because Dumbledore's death was already planned, so when Snape killed him, it wasn't actually a takeover of the wand. Because Draco was the last to disarm Dumbledore, or 'take' his wand, it recognized Draco as it's master. This is how Voldemort was ultimately killed, because Harry was using Draco's original wand. The elder wand recognized the wand as its master's, so Voldemort's killing curse was turned back upon him. However, Draco never actually had the Elder Wand in his possession. He never even knew he was the master until Harry revealed it.
At the end of Harry potter and the Half-Blood Prince Dumbledore dies Snape goes to the dark side and Harry and Ginny kiss. Hermione gets jealous of Ron and lavender being together.---- this is incorrect , the story you have provided is for Harry Potter & the half blood prince the last movie is deathly hallows in which voldemort eventually dies & is about harry searching for horcruxes
Peter was supposed to kill Harry Potter in Malfoy Manor, as Harry was trying to escape, however he hesitated and his own silver hand, given to him in Goblet of Fire by Voldemort, strangled him to death because he showed weakness.
Yes, he arranged it with Snape.
So Harry would not interfere in the plan Snape and Dumbledore had agreed on.
Albus Dumbledore was killed by Severus Snape. Although Dumbledore, who was dying anyway, had already arranged for Snape to kill him so that Draco Malfoy wouldn't have to and so that the Elder wand would not change masters. However, as Draco disarmed Dumbledore shortly before his death that part of the plan did not work.
Albus Dumbledore died after Severus Snape hit him with the killing curse. Dumbledore had previously told Snape that when the time came, it must be Snape who killed him. This was to prevent Draco Malfoy from having to do so and to also ensure that Dumbledore died the last master of the Elder wand. However, as Draco disarmed Dumbledore, that part of the plan failed.
Severus Snape joined the Death Eaters after he left Hogwarts. He was the one who overheard the prophecy and told Voldemort what he had heard. When Snape discovered who it was that Voldemort planned to kill he headed straight to Dumbledore to tell him and ask for her protection because he loved Lily (Evans) Potter.Dumbledore said he would protect them but Snape had to do something for him and Snape agreed.The plan was that Snape joined the Order of the Phoenix and remained a member of the Death Eaters. Voldemort thought he was in the Order to spy on them and give information to the Death Eaters.In actual fact, Snape was a double, double agent. He worked for the Order telling them everything the Death Eaters knew and planned and told the Death Eaters only what Dumbledore allowed him to say.Overall; he was an Order member.
Dumbledore put a cursed ring on his hand which would have killed him had Snape not stopped it. Snape told Dumbledore he only had about a year left to live and Dumbledore knew that Voldemort was plotting his death but didn't want Draco Malfoy's soul to be damaged by this. He also knew that Voldemort would want the Elder wand and that Snape needed to keep convincing Voldemort he was on his side. So, Dumbledore told Snape to kill him which meant Voldemort trusted him, Draco kept his soul intact and Dumbledore died as the last true owner of the Elder wand - although because Draco disarmed him before he died that part of the plan didn't work. Also because Dumbledore says that he would rather be killed by Snape than one of the other Death-Eaters, such as Belatrix Lestrange who, as Dumbledore put it 'like to play with their food'. Snape also made an unbreakable vow to Narcissa (or Cissy) Malfoy, to help Draco in his deed set by 'The Dark Lord', and if it should seem Draco would fail, he commit the deed himself. (The deed being to kill Albus Dumbledore)
Yes, in 1997/98 under the directions of Voldemort. It was another part of Dumbledore's plan, that Snape would make sure that the students were somewhat protected from the crueler Deatheaters.
Yes, Severus Snape killed Albus Dumbledore. This was arranged between the two of them so that Draco Malfoy wouldn't have to do it. Dumbledore also wanted to die as the last master of the Elder wand, although this part of the plan didn't work as Draco disarmed Dumbledore shortly before he was killed making Draco the master.
When snape turns on Dumbledore (at least you think he does) at the very end of the book and kills him. He actually kills him but it is all part of a plan Dumbledore had in the 7th book
Snape killed Dumbledore. It seems all part of Dumbledore's ultimate and all-transcending plan. He was on the brink of perishing anyway, due to a horcrux curse damaging him as seen by the blackening of his one arm.
Dumbledore wanted Snape to kill him because otherwise Draco Malfoy would have had to do it, or be killed. neither of which Dumbledore wanted. Because he is already slowly dieing from the Horcrux ring that he put on his finger (the reason he has a black arm) and because Voldemort ordered Drako to kill Dumbledore and Dumbledore doesn't want it on Drako's conscience. Also, Snape needed to kill Dumbledore to silence any speculation with the Death Eaters about who's side he is really on. ------------------------------------------------------------------------------------------------ Dumbledore wanted Snape to kill him so that Draco's soul wouldn't be damaged, ripped apart on his acount. When Snape asked "what about my soul?" Dumbledore replied: do you think it would affect you by helping an old man avod pain and humiliation." or something like that.
Nobody actually betrayed them, it was a plan of Dumbledore's and Snape that Snape would tell Voldemort the time and date the Order would depart with Harry. The only "betrayal" that occured was that Mundungus Fletcher disapparated when he saw Voldemort flying after him.