A jar is a rigid, cylindrical or slightly conical container, typically made of glass, ceramic, or plastic, with a wide mouth or opening that can be closed with a lid, screw cap, lug cap, cork stopper, roll-on cap, crimp-on cap, press-on cap, plastic shrink, heat sealed lidding film, an inner seal, a Tamper-evident band, or other suitable means.
Jars can be used to hold solids too large to be removed from, or liquids too viscous to be poured through, a bottle's neck; these may be foods, cosmetics, medications, or chemicals.  Glass jars--among which the most popular is the mason jar--can be used for storing and preserving items as diverse as jam, pickled gherkin, other pickles, marmalade, sun-dried tomatoes, olives, jalapeño peppers, chutneys, pickled eggs, honey, and many others.
Some regions[In what country?] have a legally mandated deposit refundable upon return of the jar to its retailer, after which the jar is recycled according to the SPI recycling code for the material.
Preserved food in Mason jars
Reusable jam jar with flip-top or bail closure
Jar made of PLA-blend bio-flex, a bioplastic
Brown-glazed jar with design of three fish. Yuan Dynasty.
PP jar of skin cream with pump dispenser