You are looking at the HTML representation of the JSON format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the JSON format, set format=json.
See the complete documentation, or API help for more information.
{
    "query": {
        "namespaces": {
            "-2": {
                "id": -2,
                "case": "first-letter",
                "*": "\u039c\u03ad\u03c3\u03bf",
                "canonical": "Media"
            },
            "-1": {
                "id": -1,
                "case": "first-letter",
                "*": "\u0395\u03b9\u03b4\u03b9\u03ba\u03cc",
                "canonical": "Special"
            },
            "0": {
                "id": 0,
                "case": "first-letter",
                "*": "",
                "content": ""
            },
            "1": {
                "id": 1,
                "case": "first-letter",
                "*": "\u03a3\u03c5\u03b6\u03ae\u03c4\u03b7\u03c3\u03b7",
                "subpages": "",
                "canonical": "Talk"
            },
            "2": {
                "id": 2,
                "case": "first-letter",
                "*": "\u03a7\u03c1\u03ae\u03c3\u03c4\u03b7\u03c2",
                "subpages": "",
                "canonical": "User"
            },
            "3": {
                "id": 3,
                "case": "first-letter",
                "*": "\u03a3\u03c5\u03b6\u03ae\u03c4\u03b7\u03c3\u03b7 \u03c7\u03c1\u03ae\u03c3\u03c4\u03b7",
                "subpages": "",
                "canonical": "User talk"
            },
            "4": {
                "id": 4,
                "case": "first-letter",
                "*": "MusicLexis",
                "subpages": "",
                "canonical": "Project"
            },
            "5": {
                "id": 5,
                "case": "first-letter",
                "*": "\u03a3\u03c5\u03b6\u03ae\u03c4\u03b7\u03c3\u03b7 MusicLexis",
                "subpages": "",
                "canonical": "Project talk"
            },
            "6": {
                "id": 6,
                "case": "first-letter",
                "*": "\u0391\u03c1\u03c7\u03b5\u03af\u03bf",
                "canonical": "File"
            },
            "7": {
                "id": 7,
                "case": "first-letter",
                "*": "\u03a3\u03c5\u03b6\u03ae\u03c4\u03b7\u03c3\u03b7 \u03b1\u03c1\u03c7\u03b5\u03af\u03bf\u03c5",
                "subpages": "",
                "canonical": "File talk"
            },
            "8": {
                "id": 8,
                "case": "first-letter",
                "*": "MediaWiki",
                "subpages": "",
                "canonical": "MediaWiki"
            },
            "9": {
                "id": 9,
                "case": "first-letter",
                "*": "\u03a3\u03c5\u03b6\u03ae\u03c4\u03b7\u03c3\u03b7 MediaWiki",
                "subpages": "",
                "canonical": "MediaWiki talk"
            },
            "10": {
                "id": 10,
                "case": "first-letter",
                "*": "\u03a0\u03c1\u03cc\u03c4\u03c5\u03c0\u03bf",
                "canonical": "Template"
            },
            "11": {
                "id": 11,
                "case": "first-letter",
                "*": "\u03a3\u03c5\u03b6\u03ae\u03c4\u03b7\u03c3\u03b7 \u03c0\u03c1\u03bf\u03c4\u03cd\u03c0\u03bf\u03c5",
                "subpages": "",
                "canonical": "Template talk"
            },
            "12": {
                "id": 12,
                "case": "first-letter",
                "*": "\u0392\u03bf\u03ae\u03b8\u03b5\u03b9\u03b1",
                "subpages": "",
                "canonical": "Help"
            },
            "13": {
                "id": 13,
                "case": "first-letter",
                "*": "\u03a3\u03c5\u03b6\u03ae\u03c4\u03b7\u03c3\u03b7 \u03b2\u03bf\u03ae\u03b8\u03b5\u03b9\u03b1\u03c2",
                "subpages": "",
                "canonical": "Help talk"
            },
            "14": {
                "id": 14,
                "case": "first-letter",
                "*": "\u039a\u03b1\u03c4\u03b7\u03b3\u03bf\u03c1\u03af\u03b1",
                "canonical": "Category"
            },
            "15": {
                "id": 15,
                "case": "first-letter",
                "*": "\u03a3\u03c5\u03b6\u03ae\u03c4\u03b7\u03c3\u03b7 \u03ba\u03b1\u03c4\u03b7\u03b3\u03bf\u03c1\u03af\u03b1\u03c2",
                "subpages": "",
                "canonical": "Category talk"
            }
        }
    }
}