mORMot Open Source

I found some rare usages of the keyword "object",
type
  TDiffCalc = object
    FirstDiffLineIndex,
    linesAdd, linesMod, linesDel: integer;
    procedure Execute(Text1, Text2: string; Memo1, Memo2: TMemoEx;
      ShowDiffsOnly: boolean);
  end;

from line 32 of ProjectFormViewTwo.pas,and also

TSQLStatementCached = object
Cache: TSQLStatementCacheDynArray;
Count: integer;
Caches: TDynArrayHashed;
DB: TSQLite3DB;
procedure Init(aDB: TSQLite3DB);
function Prepare(const GenericSQL: RaWUTF8): PSQLRequest;
procedure ReleaseAllDBStatements;
end;

from page 109 of Synopse mORMot Framework SAD 1.18.pdf, I just wonder that why "object" is necessary here and if I could use "class" or "record" instead.