Chip can be identified by his small black "chocolate chip" nose and a single front tooth, whereas Dale has a larger nose which is red, and two adjacent front teeth. Chip is also usually the more logical and cunning of the two, with Dale being the more dim-witted.
While they most frequently appeared in theatrically-released cartoons under the Donald Duck and Pluto series, they were also featured in three shorts under their own banner, "Chip and Dale"—these were Chicken in the Rough, Two Chips and a Miss and The Lone Chipmunks.
The duo also starred in their own television series, Chip 'n Dale Rescue Rangers, as leading protagonists.
Chip and Dale first appeared in a 1943 Pluto cartoon titled Private Pluto. In this appearance, they look a lot more like realistic chipmunks and did not have names. The two then-nameless twin chipmunks were never intended to be used again after that short, but when Walt Disney needed new characters to challenge Donald Duck, Walt decided to revive these two chipmunks, leading them to acquire their now-familiar names and personalities. Ever since, they have appeared primarily in Donald Duck and Pluto cartoons.
Chip and Dale became so popular that they were able to star in their own series of cartoons, joining Mickey Mouse, Donald Duck, Goofy and Pluto. Only three shorts were created in that series. The first was Chicken in the Rough, where Dale becomes trapped in a chicken coop. The next and most famous one was Two Chips and a Miss, where they go out to a night club and battle for the attention of female chipmunk Clarice. The last was The Lone Chipmunks, where Chip 'n' Dale foil the outlaw Pete.
Their names are a pun on the name "Chippendale" (a reference to furniture-maker Thomas Chippendale). This was suggested by Bill "Tex" Henson, a screenwriter at the studio.
The classic voices of Chip and Dale were mostly provided by Helen Silbert, Dessie Flynn/Dessie Miller and James MacDonald. The earliest voices of the chipmunks were provided by female office staff, without credit.
In Private Pluto, the chipmunks' speech was created by speeding up sound clips of normal speech. In a number of the shorts that followed, many of these same sound clips were re-used again and again, though later shorts used new dialogue specifically recorded for them.
At one point in Winter Storage, Chip and Dale get into an argument while caught in a trap. When the scene switches to an outside view of the box (with Donald Duck sitting on the box), the dialogue being heard is actually a sped-up segment of the voice-over narration from the Goofy short A Knight for a Day.
Since 1988, Chip has been voiced by Tress MacNeille and Dale has been voiced by Corey Burton. However, in Mickey Mouse Works, House of Mouse, the first season of Mickey Mouse Clubhouse and the Have a Laugh! versions of the classic shorts, Tress voiced both chipmunks.
Chip is the brains of the duo and thus is shown to be clever, fearless and a little bossy. Unlike his best friend, he's a fast thinker and far more active. When dealing with Donald, Chip shows to be much more of a threat than Dale, both mentally and physically. In Rescue Rangers, Chip constantly thinks about being on duty to the point where he is thought to not know how to be fun; because of such, Dale's blundering causes him nothing but headaches.
Dale is sometimes lazy, dim-witted and clumsy. In earlier appearances, he was completely foolish to the point where he can truly be called an idiot. In later years, that aspect of his personality was toned down to just being carefree, fun-loving, and goofy. In Rescue Rangers, Dale wears a Hawaiian shirt, possibly to show how relaxed his personality is; he gets along easier with Monterey Jack and Zipper than Chip.
While the two are nearly inseparable and count each other as their closest friends, the one thing that can tear them apart is a romantic interest. They have been known to have feelings for the same girl most of the time and battle each other for the affections of the girl in question. In Rescue Rangers, both are in love with Gadget, but can't seem to be open about their feelings.