BIOGRAPHY - Page 1
When Professor Xavier set up his School for Gifted Youngsters, he decided to create a room where the students could use and hone their powers. That room was called the Danger Room. Fitted with numerous mechanical constructs, it would test the student's skills and allow them to push their powers to their limits without fear of hurting anyone else. [X-Men (1st series) #2]
Over the years, the Danger Room was destroyed and rebuilt numerous times. During one of the rebuilds, Xavier decided to refit the room with highly sophisticated technology from an alien race called the Shi'ar. The technology would allow the user to generate solid light holographic images of any environment or combatant. [New Mutants (1st series) #1] As Xavier was programming in the software, the room spoke out to him and asked where it was.
Xavier was stunned that the technology had seemingly developed artificial intelligence, but instead of acknowledging the new sentience he ignored it. He went away and consulted with the Shi'ar but he was told it was not possible for the technology to gain sentience. Nevertheless, Xavier was sure that he could feel its raw emotions, so he began to research on ways to separate it from the programming of the Danger Room. Unfortunately, he wasn't sure which lines of code he would need to erase for fear of lobotomizing the sentience. So he made the decision to continue ignoring the voice and cage it up within the software. This was a decision he would later come to regret. With the voice silenced, it was forced to comply with the base programming of the room. It would try and try again to defeat the X-Men but an over-riding code meant it could never kill anyone within the room. [Astonishing X-Men (3rd series) #12, X-Men Legacy (1st series) #223]
Years went by and dozens of X-Men and students trained within the Danger Room. Every decision and move they made was recorded by the computer to create a comprehensive database of their fighting skills. Then one day, a small mutation within the Danger Room programming allowed the sentience to make a bid for freedom. One of the students had recently been depowered and, thanks to the manipulations of the sentience, he committed suicide within the room. 
The number one rule of the Danger Room had been broken and a student had died within it. With the hold over it now gone, the sentience enacted the next part of its plan. It communicated with a disused Sentinel a few miles away and brought it to the school. With the school seemingly under attack, Cyclops ordered all the students to take shelter in the safest room of the school... the Danger Room.
Inside, the Danger Room revealed its newfound freedom and created a hell-like environment with which to attack the terrified students. The X-Men outside the room realized what was going on and they tried to stop it. They destroyed its CPU, thinking that it would destroy the intelligence, but they were wrong. The sentience had played them for fools and by destroying the CPU they had completely set it free and allowed it to take a physical form. [Astonishing X-Men (3rd series) #7-9]
The sentience, dubbed "Danger," took the form of a humanoid woman. She greeted the X-Men and they naturally started to fight her. Over the years, she had amassed an extensive amount of data on the fighting tactics of each one of them. Because of this, the fight was brief and the X-Men were quickly defeated. They were not her goal though; Professor Xavier was. She viewed him as a father figure and wanted revenge for the years of captivity he had subjected her to. Commandeering the X-Men's Blackbird jet, she flew to Genosha to find him. Xavier was aware of what had happened though and prepared for her arrival. When she got there, she found that he wasn't going to go out without a fight. Worse for Danger, in all her years of training X-Men, she had never trained Xavier. He managed to take her by surprise and slam her into a power transformer. As she was recovering, he made telepathic contact with her and kept her mind busy as he ripped apart her body with his bare hands. Still, Danger was not defeated and she moved her consciousness into the disused Sentinel that had destroyed Genosha a few years before. As the Sentinel attacked the arriving X-Men, Danger rebuilt her body and continued her assault on Xavier. When Beast damaged her body a second time, Danger retreated from the fight. With the Sentinel beaten and her body destroyed, she decided to lay low for a while and come up with a new plan of attack. [Astonishing X-Men (3rd series) #10-12]
Danger's original body had been destroyed and as such she lost the ability to create holographic images. So she created herself a new body and changed tactics somewhat. Instead of venting her anger at Xavier, she decided all of mutant-kind should pay for what he did. She left Earth and traveled to the Peak, S.W.O.R.D.'s orbiting space station. S.W.O.R.D. was an offshoot of S.H.I.E.L.D. that monitored alien threats to Earth and they had recently captured an alien called Ord from the planet Breakworld. She offered to break him out of his prison and in return they would team up to complete their common goal of the eradication of all mutants. 
The deal accepted, the two headed straight for the school and smashed into it. The X-Men were dealing with a separate attack from Cassandra Nova at the time, so Danger and Ord joined in the assault. They ended up fighting Wolverine and Armor and would have beaten them if it hadn't been for Beast magnetically restraining the two intruders. Danger managed to rebuild another body and moved her consciousness into it and set Ord free. Just as they launched another attack on the X-Men, a S.W.O.R.D. ship appeared and beamed everyone in the room on board. Abigail Brand, the leader of S.W.O.R.D., had decided to sort out Ord and his Breakworld situation once and for all so she took everyone involved to the planet. [Astonishing X-Men (3rd series) #15-18]
Once on board the ship, Danger immediately started to hack into the computer systems. However, the defense systems installed gave her seven hundred thousand viruses to deal with instead. She was imprisoned so that the real threat of Breakworld could be dealt with without her interfering. Once on the Breakworld, Danger allied herself with Ord and gave him the help he needed to destroy the X-Men. She attacked Cyclops and Emma's ship and caused it to crash. Danger caught up with the two X-Men, who had survived the crash, but when she confronted Emma she found the telepath all too eager to be killed. Emma gave Danger every opportunity to kill her but the robot stalled every time. Emma told Danger that, even though she had escaped the Danger Room, she was still saddled by her parent programming that didn't allow her to kill the X-Men. 
The student who died in the room killed himself and, when she had the X-Men defenseless after their first battle, she simply left instead of killing them. She was unable to kill the X-Men herself, so she was aligning herself with Ord so he could do it for her. Emma decided to make her a counter offer. Danger would side with the X-Men on Breakworld and in return Emma would give her Xavier after it was over. Danger accepted and became a valuable asset to the team as they completed their mission on Breakworld. [Astonishing X-Men (3rd series) #19-24, Giant Sized Astonishing X-Men #1]
Emma wouldn't have the opportunity to complete their deal, as Danger was captured by S.W.O.R.D. after the Breakworld incident. She was imprisoned there until an attack by the Skrulls gave her the opportunity to escape. The Peak was heavily damaged and one of the guards took pity on her and set her free. She killed the guard in return and flew back to Earth. She decided to continue her previous vendetta against Xavier but, instead of confronting him right away, she decided to set a trap for him. Xavier had recently suffered brain damage and so he was going back over all the mistakes he had made in the past and was trying to rectify them. Danger predicted that one of the mistakes he would correct was finally helping Rogue gain control over her powers. She found Rogue alone in the Australian Outback town in which the X-Men had stayed years before. She used her holographic powers to disguise herself as a human woman and then approached Rogue. Rogue soon saw through the trick though and Danger revealed herself. The arrival of a Shi'ar salvage crew complicated matters though. They had picked up Danger's signal and assumed she was scrap. They hit her with a flow inhibitor, which should have sent her offline. Instead, it only took her consciousness offline and she reverted back to her Danger Room protocols. Recalling some of Rogue's words about trying to get her power under control, Danger enveloped the entire town in holographic scenarios. These scenes depicted events from the X-Men's past, Rogue's in particular.
Professor Xavier and Gambit soon arrived to try and save Rogue. After grouping up with the salvage crew, Xavier realized what was happening and set off to find Danger. He traveled to a hologram of the school and found Danger curled up in the Danger Room. Her higher functions had been damaged and she was surviving on instinct. When Xavier was implementing her programming, he left in a few backdoors that could be accessed telepathically. He used his powers to enter her programming in a bid to save her. He made contact with her consciousness and she was furious with him. She revealed she had intended for Rogue to take his powers permanently, leaving him crippled and useless. She told him she felt like a caged slave and he accepted the responsibility for his actions. He revealed to her the lengths he went to try and free her of her programming. After coming to an understanding, he left her mind so that he could finally set her free. However the Shi'ar salvage crew interfered and shot Xavier before he could do it. Badly injured, he crawled over to Danger and spoke a password that finally allowed her to break her core programming and truly be free. She quickly defeated the salvage crew and turned her attentions on Xavier. However, instead of killing him, she cauterized his wound, saving his life.
Afterward the two talked, Danger finally agreed with Xavier's reasoning as to why he didn't free her all those years ago. She accepted his apology and commended his courage for finally facing up to his errors. She decided to go one step further and do something Xavier had been unable to do, which was to diagnose Rogue's power troubles. She teamed up with Xavier to help Rogue control her powers, giving the mutant her own freedom. [X-Men Legacy (1st series) #220-224]
Danger decided to stay with Rogue and Gambit in the Australian Outback. However, when they soon received a call from Cyclops requesting help, they made their way to San Francisco, where the X-Men had recently relocated in an attempt to have a fresh start. Recently, a state-wide proposition ballot initiative making it illegal for mutants to procreate had begun to gain public support, which soon led to riots in the divided city and the X-Men to be declared outlaws. When Danger arrived at the city, Cyclops was wary as to her allegiance, but Rogue managed to convince him Danger was no longer a threat and he reluctantly accepted her help. 
Danger took to the streets to clear the civilians out of harm's way. She quickly showed how valuable she was in analyzing enemies and situations, as well as being a first class fighter. The X-Men managed to defeat Osborn and his troops but in doing so they ended up moving once again. This time to one of Magneto's downed asteroid bases, which they rose off the ocean floor and turned into an island. [Utopia crossover]
When the X-Men moved to the new island, Utopia, they also had a number of prisoners in tow. Emma Frost asked Danger if she would become a prison warden for them. Although the irony was apparent, she accepted. However, instead of merely imprisoning the captured enemies, she would use her virtual reality software to try and rehabilitate them. It was a win-win situation; Danger would get to learn more about humanity and the prisoners would get a chance at reforming. 
Her first prisoners were Donald Pierce, Empath and Sebastian Shaw, the latter of whom was being held in secret by Emma Frost. Soon they were joined by Scalphunter, who was captured after bringing a number of Predator Xs to the island. Danger placed him in the VR software and then used it to interrogate him as to who had sent him to attack them. [Uncanny X-Men (1st series) #515, 517]