Canning foods in Mason jars is a great way to preserve your garden produce. It should be done with tested and approved recipes to ensure the safety of the product. The Ball Blue Book is an excellent resource. Also you may find that your extension service has information on canning for your locale. The reason locale is important is because of the altitude change. Canning times increase as the altitude increases because the boiling temperature of water is lower at higher altitudes. Also check out this [url=https://nchfp.uga.edu/publications/publications_usda.html]LINK[/url].
This paper describes the proper procedure of using both water bath canners and pressure cookers. It is a great resource.