Scientists and engineers spend a significant portion of their professional lives writing, because communicating ideas in writing is central to the process of creating and publicizing knowledge. Lab reports are one important way they communicate the results of their work. Adding new knowledge to a field is the collective effort of many people, each contributing small pieces of information and building on the work of others. Although scientists and engineers might work alone or in small groups in a lab, if they want to contribute to their fields, they must convince readers that their findings are valid. For this reason, the ability to write clearly and persuasively is both necessary and valued in the sciences and engineering.