A formal shirt or dress shirt is a clothing item with a collar and opens full length at the front and is fastened with buttons or shirt studs. Formal shirts are made of woven cloth like cotton, linen, silk, wool or with fibers having a polyester blend and are worn by men under a coat or a jacket for formal occasions, but can also be worn casually. The formal shirts are indicated by the style of collar like spread collars that are generally a little broad, narrow or straight collars and the button down collars that are fastened on the front of the shirt with small buttons. Sometimes formal shirts have a collar of a contrasting color generally white on a colored, striped or patterned shirt. Collar interlining can be fused or non-fused depending on the stiffness or softness you require for greater comfort. The cuffs of formal shirts are fastened with buttons or with cuff links or can be just folded back. The shirts are stitched in a way that the yolk or back shoulder of the shirt may have a different pattern or the stripe or check can be placed in a contrasting way. The quality of a shirt can also be checked how well the check and stripe pattern is lined at the seams. For formal shirts the buttons should be mother-of-pearl because of their luster but other buttons like horn or plastic can also be used. Always make sure that the top button is slim to facilitate buttoning your shirt. A formal white shirt looks really good as an evening wear under a coat or otherwise too.