These decal terms are fairly synonymous in nature.
Technically decals, stickers and graphics are all terms that can be used to describe an adhesive backed product that will be stuck onto a surface to inform, advertise, personalize, identify, market or brand, etc. In the printing world you can mention decals, stickers or graphics and be understood as decals, stickers and graphics are all adhesive in nature and interchangeable but can be broken down into specifics as well. Decal is a loose term, so more than likely your sign company will ask you more questions to determine what "kind of" decal you need before you order custom decals from them.
For lots of people this is the go to word for all things decal related like vehicle decals, window decals, floor decals, wall decals, etc. A decal can be square cut, oval cut, rectangular cut, circular cut or cut-to-shape. Though most commonly the word decal refers to any adhesive decal product that will be die-cut or cut-to-shape. Decals are frequently printed on durable vinyl material for indoor or outdoor use and applied to any non-porous smooth surface for commercial, personal or recreational purposes.
Stickers typically cover decals that have simple shapes like square, rectangular, circular or oval. Stickers though can still be referred to as decals when they need to be cut-to-shape as well. People looking for stickers tend to be searching for a short-term use product that is printed on paper stock, although for a longer lasting sticker decal we offer two different vinyl stocks great for outdoor use. Labels also fall into the sticker and decal category. Labels can also be printed on paper stock or vinyl to meet your decal needs.
When referring to decals, utilizing the graphics term, it usually entails a combination of images, logos and text that need to be cut-to-shape or die-cut. On the other hand, in reference to graphics, your sales representatives might be asking about artwork. The term/word graphics in the print industry actually has a dual meaning. So while your car, window or wall graphics reference digital decals and/or cut vinyl lettering, you may be asked to supply graphics as well (the files to produce your decal graphics from.)
Cut vinyl lettering or digitally printed lettering are also grouped into the "decal" group. Cut vinyl lettering can be text, logos, simple shapes or numbers that are cut out of colored vinyl, into a specific shape, without a background; or the same cut-out effect can be achieved through digital printing, if your decal needs include specific colors or color gradients, that our cut vinyl colors can't accommodate or achieve.