Literary devices are used regularly in writing to increase the effectiveness of a description or explanation. Examples include favorites such as simile, metaphor, personification and various others. In "The Outsiders," foreshadowing, flashback, and pathos are used to add emphasis to the build-up to Johnny's mugging and the effect that the attack has on Johnny, which is very important as it explains Johnny's state of mind later when he kills Bob, a Soc while defending Ponyboy and then inference is used when Ponyboy begins to describe the actual attack.
In chapter 1, before he fully describes Johnny's mugging, Ponyboy refers to it several times as he considers how Johnny has changed since the mugging. He says, "Johnny was scared of his own shadow after that." Ponyboy describes the "nervous, suspicious look in his eyes" even though Johnny was used to being beaten by his own father. In chapter 2, when Two-Bit gives Johnny a fright, the effects are severe as Ponyboy describes Johnny's reaction to Two-Bit's actions: "His breath was coming in smothered gasps." The reader pities Johnny's home situation, and for Johnny to suffer a beating at the hands of the Socs as well intensifies the reader's feelings towards Johnny (empathy, pathos) which again is important in understanding his reaction to events which unfold later.
Inference is used effectively as Ponyboy describes the actual mugging. The reader knows immediately that Johnny, "the dark motionless hump on the other side of the lot," has been beaten up and "the gang sensed what had happened" as Johnny tries to explain that there "was a whole bunch of them." Without actually saying so, it is obviously the Socs, the rival gang in the neighborhood, that has hurt Johnny. For Johnny to carry a "switchblade" after that event in order to apparently protect himself, is significant and foreshadows what will follow.
As already mentioned, the main literary device used is that of flashback, when the narrator leaves the present moment to relate something that happened in the past. We can also say that Ponyboy, when narrating the story of Johnny's beating, uses a careful build-up technique, revealing what happened in stages. For instance, the first clue that something bad happened to Johnny is when Ponyboy finds his jacket which is described as having a stain 'the colour of rust' on it. The stain of course is blood, but Ponyboy chooses to refer to it obliquely. The badly-beaten Johnny first appears as a 'dark motionless hump' rather than as a person; this is an example of a de-humanizing image. In this way Ponyboy builds up slowly to the terrible revelation of the savage beating Johnny received at the hands of the Socs. The actual beating is never shown at all: we only see the grim results of it in the form of Johnny's battered body and bloodstained jacket. It is obviously a very painful memory for Ponyboy, which is no doubt why he relates it in a somewhat roundabout manner to the sympathetically-listening Cherry.
As already mentioned in another answer, the story of this incident also uses the technique of foreshadowing, which is to say it hints at an event later in the book. This is when Johnny declares that 'he'd kill the next person who jumped him'. He ends up doing just that.
Hinton uses the device of flashback, which is when the narrator leaves the present time to tell about something that happened in the story's past. During the description itself, Hinton uses imagery to describe the state the boys found Johnny in and the way the boys felt when they found him.
I'm reading this book in my reading/writing class and it actually does use flashback for refering to Johnny's beating with the Socs. It's actually a pretty good book. :)
The author had used flashback, backstory, and foreshadow. the author had flashbacked about the story of what had happen to Johnny, used backstory which added more detailes in the story, and foreshadowed that if anything like that happened again, he would kill that person. thoses three are the literary devices the author used to describe Johnny's mugging. You dig? :)