Warning: Setting the filter to anything other than "Safe" will expose you to content intended for a mature audience and NOT FOR CHILDREN under the age of 18 and certainly not under 13.
The content are categorized according to what the author believes the content belongs to. Creative content is subjective. Your views and beliefs may vary. Exercising caution is always advised when viewing content on the Internet.
If you are sharing a particular page that is normally hidden and require you to change a filter for, whoever you are sharing it with will not be able to see it under normal cases unless they also change the filter.
Viewing content generally safe with no nudity, most of the sexual implications filtered out, content of characters in mostly non sexual poses will be clothed in at least bikini, swimsuits, and adequate enough clothing and viewing the safe versions to mature pictures.
Viewing content with nudity, exposed genitals (aroused or not) and "female presenting nipples" most likely in provocative poses. Content will also include characters in attire such as underwear and lingerie with the intention to be sexually explicit and arousing. Content will also include sexual interaction, activity, implications, bodily fluids, self pleasure and certain fetishes.