You are looking at the HTML representation of the PHP format.
HTML is good for debugging, but probably is not suitable for your application.
See complete documentation, or API help for more information. 
a:1:{s:5:"query";a:1:{s:10:"namespaces";a:18:{i:-2;a:4:{s:2:"id";i:-2;s:4:"case";s:12:"first-letter";s:1:"*";s:7:"Médiá";s:9:"canonical";s:5:"Media";}i:-1;a:4:{s:2:"id";i:-1;s:4:"case";s:12:"first-letter";s:1:"*";s:11:"Špeciálne";s:9:"canonical";s:7:"Special";}i:0;a:4:{s:2:"id";i:0;s:4:"case";s:12:"first-letter";s:1:"*";s:0:"";s:7:"content";s:0:"";}i:1;a:5:{s:2:"id";i:1;s:4:"case";s:12:"first-letter";s:1:"*";s:8:"Diskusia";s:8:"subpages";s:0:"";s:9:"canonical";s:4:"Talk";}i:2;a:5:{s:2:"id";i:2;s:4:"case";s:12:"first-letter";s:1:"*";s:8:"Redaktor";s:8:"subpages";s:0:"";s:9:"canonical";s:4:"User";}i:3;a:5:{s:2:"id";i:3;s:4:"case";s:12:"first-letter";s:1:"*";s:21:"Diskusia s redaktorom";s:8:"subpages";s:0:"";s:9:"canonical";s:9:"User talk";}i:4;a:4:{s:2:"id";i:4;s:4:"case";s:12:"first-letter";s:1:"*";s:9:"Gaya Wiki";s:9:"canonical";s:7:"Project";}i:5;a:5:{s:2:"id";i:5;s:4:"case";s:12:"first-letter";s:1:"*";s:20:"Diskusia k Gaya Wiki";s:8:"subpages";s:0:"";s:9:"canonical";s:12:"Project talk";}i:6;a:4:{s:2:"id";i:6;s:4:"case";s:12:"first-letter";s:1:"*";s:6:"Súbor";s:9:"canonical";s:4:"File";}i:7;a:5:{s:2:"id";i:7;s:4:"case";s:12:"first-letter";s:1:"*";s:18:"Diskusia k súboru";s:8:"subpages";s:0:"";s:9:"canonical";s:9:"File talk";}i:8;a:5:{s:2:"id";i:8;s:4:"case";s:12:"first-letter";s:1:"*";s:9:"MediaWiki";s:8:"subpages";s:0:"";s:9:"canonical";s:9:"MediaWiki";}i:9;a:5:{s:2:"id";i:9;s:4:"case";s:12:"first-letter";s:1:"*";s:20:"Diskusia k MediaWiki";s:8:"subpages";s:0:"";s:9:"canonical";s:14:"MediaWiki talk";}i:10;a:4:{s:2:"id";i:10;s:4:"case";s:12:"first-letter";s:1:"*";s:9:"Šablóna";s:9:"canonical";s:8:"Template";}i:11;a:5:{s:2:"id";i:11;s:4:"case";s:12:"first-letter";s:1:"*";s:20:"Diskusia k šablóne";s:8:"subpages";s:0:"";s:9:"canonical";s:13:"Template talk";}i:12;a:4:{s:2:"id";i:12;s:4:"case";s:12:"first-letter";s:1:"*";s:5:"Pomoc";s:9:"canonical";s:4:"Help";}i:13;a:5:{s:2:"id";i:13;s:4:"case";s:12:"first-letter";s:1:"*";s:17:"Diskusia k pomoci";s:8:"subpages";s:0:"";s:9:"canonical";s:9:"Help talk";}i:14;a:4:{s:2:"id";i:14;s:4:"case";s:12:"first-letter";s:1:"*";s:10:"Kategória";s:9:"canonical";s:8:"Category";}i:15;a:5:{s:2:"id";i:15;s:4:"case";s:12:"first-letter";s:1:"*";s:22:"Diskusia ku kategórii";s:8:"subpages";s:0:"";s:9:"canonical";s:13:"Category talk";}}}}