The first author is generally the individual who made the most substantial intellectual contribution to the work, such as conceiving the study, collecting and analyzing experimental data, and writing the report. In some cases, it may be someone other than the senior author; for example, if there are more than two co-authors, then they can be divided up according to their respective roles in making the discovery. However, usually the person or people who make the greatest intellectual impact on the work are also listed as authors. In academia, the order of authors is often considered important for credit purposes. For example, in the case of joint papers, only the first author will typically receive credit for the work. If two or more people make equal contributions to the work, then they should be listed in alphabetical order by last name. In industry, however, the order of authors does not matter for credit purposes. Therefore, in industry, you do not have to worry about being given less credit because another person was listed first. Instead, try to balance giving appropriate credit to others while still keeping the list short. For example, if one person came up with the concept and another performed most of the experiments, then they should be listed as authors appropriately.