Simplified Chinese is the result of official reforms in the People's Republic of China, especially character lists issued in the 1950s and 1960s. The public goal was literacy. If common characters took fewer strokes, and if teachers did not have to police as many variant shapes, more students might finish school able to read a newspaper.
That argument is historical, not a scoreboard. Taiwan, Hong Kong and Macau kept Traditional characters and also run literate societies. The useful question for a file you have to convert is not "which side won." It is "which official list does this audience use, and what did the lists actually change?"
What the reformers did
The work was not a single clever idea. Several methods sit side by side on the same page of a modern file.
Stroke reduction. Many forms keep the same skeleton with fewer marks. 國 to 国, 門 to 门, 書 to 书, 馬 to 马 are the examples everyone learns first.
Popular or handwritten shapes made official. Some "new" forms were already common in cursive or in older informal writing. Making them official meant the classroom stopped treating them as sloppy.
Mergers. Some Traditional characters that used to be distinct were folded into one Simplified shape. 后, 发, 面 and 干 are famous later problems for software, because going back to Traditional requires a choice. See one-to-many mappings.
Leaving many characters alone. Plenty of graphs are the same in both systems. A converter still walks the whole string, because the ones that differ are mixed in with the ones that do not.
Reformers also argued about how far to go. Later adjustments and unused proposals exist in the historical record. Daily software does not replay those committee debates. It applies the living lists as dictionaries.
Who adopted the lists
Mainland China teaches and prints Simplified characters as the default. Singapore later adopted Simplified characters for most official and school use. Malaysia's Chinese education has its own history, but much contemporary teaching material is Simplified.
Taiwan did not adopt the PRC lists. Hong Kong and Macau kept Traditional characters in public life, even as people there read Simplified text online. Many overseas newspapers, temples and Saturday schools stayed Traditional because that is what their founders printed.
Why Traditional Chinese is still used is the companion page. Simplified vs Traditional Chinese is the practical usage map.
Simplification is not a return to antiquity
It is tempting to say Simplified forms are "closer to the original pictures." Sometimes a reduced shape happens to look a little more like an old graph. Often it does not. Oracle bone and seal forms are not the parent of the 1960s lists. Clerical and regular script already stood in between.
Simplification is another official standard, like earlier dictionary projects. It uses the same character tradition. It does not rewind writing to Shang bones.
Handwriting remains a separate layer in both regions. People in Simplified-using cities still write faster personal forms. People in Traditional-using cities do too. A converter changes published standards, not the way a hand moves.
Why converters exist
Once two official sets are in daily use, publishers need mechanical help. A 300-page manual cannot be rewritten glyph by glyph. OpenCC is one of those tools. It does not explain 1950s policy. It applies dictionaries, including regional Traditional targets for Taiwan and Hong Kong.
That is also why conversion is not a cultural argument. Running Simplified to Traditional (Taiwan) does not declare a preference for one history. It produces the character set a Taiwan reader expects.
If you need the working sequence, use Simplified to Traditional or Traditional to Simplified. If you need the dropdown explained, use OpenCC conversion types.
Frequently asked questions
Were Simplified characters invented from nothing? No. Many come from existing popular forms or systematic stroke cuts. Some mergers are new as official combinations even when the shapes are old.
Did simplification make Chinese easy? It reduced stroke counts for many common graphs. Literacy also depends on schools, print, and time. Characters are still a large inventory.
Is every shorter character a Simplified character? No. Japanese shinjitai and informal shorthand are different stories. Do not run Japanese through OpenCC.
Why do some people say simplification destroyed meaning? Because some phonetic or semantic hints became less visible, and because mergers collapsed distinctions. Other people find the shorter forms easier to write. Both observations can be true for different characters.
Can I see which method was used on a given character? Specialist charts classify them. For publishing, you only need to know whether the pair is one-to-one or a merger that needs proofreading.