I've been using Wikipedia to learn for as long as I can remember and have been a registered user since 2010.
I expand knowledge on topics such as geographic locations, ethnic groups, languages, world history, politics, medicine, genetics, pathology, taxonomy and occasionally music. Otherwise, I build article structure or integrate articles more into Wikipedia and clean up grammatical errors, missing or inappropriate hyperlinks, wording, ambiguity or comprehensibility, neutral point of view and layout as well as adding redirects or other fixes. I also occasionally create articles, typically from red links but sometimes not, in order to add to an area of low coverage. Other things I do include adding TemplateData to templates, adding short descriptions, adding WikiProject templates to talk pages, adding/updating article assessments, fixing/improving templates and occasionally signing unsigned talk page comments.
I normally come across the pages I edit in my everyday research. These often include articles that were last edited a long time ago, stubs, articles without sources and other obscure articles.
I upload files to Wikimedia Commons. Most of these have been linguistic vector image maps I've created, usually where no map existed before; my own photos of notable landmarks; and third-party free-use medical images under CC-BY or CC-BY-SA licences. I've also uploaded various other miscellaneous free-use files and own diagrams, and sometimes I've vectorised existing maps, cropped photos or otherwise improved existing files.
I've also edited and created some articles on Wiktionary and the French Wikipedia and edited some others on other wikis.
Gadgets I recommend other users enable (as of 2020)
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