A pond is a body of water shallow enough to support rooted plants. Many times plants grow all the way across a shallow pond. Water temperature is fairly even from top to bottom and changes with air temperature. There is little wave action and the bottom is usually covered with mud.
Plants can, and often do, grow along the pond edge.
The amount of dissolved oxygen may vary greatly during a day. In really cold places, the entire pond can freeze solid. Cattails are a familiar site in North America. Cattails are aquatic plants common in creeks, ditches, and ponds. A lake is bigger than a pond, and is too deep to support rooted plants except near the shore.