You are looking at the HTML representation of the TXT 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 TXT format, set format=txt.
See the complete documentation, or API help for more information.
Array
(
    [warnings] => Array
        (
            [txtfm] => Array
                (
                    [*] => format=txtfm has been deprecated. Please use format=jsonfm instead.
                )

        )

    [query] => Array
        (
            [namespaces] => Array
                (
                    [-2] => Array
                        (
                            [id] => -2
                            [case] => first-letter
                            [*] => Media
                            [canonical] => Media
                        )

                    [-1] => Array
                        (
                            [id] => -1
                            [case] => first-letter
                            [*] => Special
                            [canonical] => Special
                        )

                    [0] => Array
                        (
                            [id] => 0
                            [case] => first-letter
                            [*] => 
                            [content] => 
                        )

                    [1] => Array
                        (
                            [id] => 1
                            [case] => first-letter
                            [*] => Talk
                            [subpages] => 
                            [canonical] => Talk
                        )

                    [2] => Array
                        (
                            [id] => 2
                            [case] => first-letter
                            [*] => User
                            [subpages] => 
                            [canonical] => User
                        )

                    [3] => Array
                        (
                            [id] => 3
                            [case] => first-letter
                            [*] => User talk
                            [subpages] => 
                            [canonical] => User talk
                        )

                    [4] => Array
                        (
                            [id] => 4
                            [case] => first-letter
                            [*] => Leading practice
                            [subpages] => 
                            [canonical] => Project
                        )

                    [5] => Array
                        (
                            [id] => 5
                            [case] => first-letter
                            [*] => Leading practice talk
                            [subpages] => 
                            [canonical] => Project talk
                        )

                    [6] => Array
                        (
                            [id] => 6
                            [case] => first-letter
                            [*] => File
                            [canonical] => File
                        )

                    [7] => Array
                        (
                            [id] => 7
                            [case] => first-letter
                            [*] => File talk
                            [subpages] => 
                            [canonical] => File talk
                        )

                    [8] => Array
                        (
                            [id] => 8
                            [case] => first-letter
                            [*] => MediaWiki
                            [subpages] => 
                            [canonical] => MediaWiki
                        )

                    [9] => Array
                        (
                            [id] => 9
                            [case] => first-letter
                            [*] => MediaWiki talk
                            [subpages] => 
                            [canonical] => MediaWiki talk
                        )

                    [10] => Array
                        (
                            [id] => 10
                            [case] => first-letter
                            [*] => Template
                            [canonical] => Template
                        )

                    [11] => Array
                        (
                            [id] => 11
                            [case] => first-letter
                            [*] => Template talk
                            [subpages] => 
                            [canonical] => Template talk
                        )

                    [12] => Array
                        (
                            [id] => 12
                            [case] => first-letter
                            [*] => Help
                            [subpages] => 
                            [canonical] => Help
                        )

                    [13] => Array
                        (
                            [id] => 13
                            [case] => first-letter
                            [*] => Help talk
                            [subpages] => 
                            [canonical] => Help talk
                        )

                    [14] => Array
                        (
                            [id] => 14
                            [case] => first-letter
                            [*] => Category
                            [canonical] => Category
                        )

                    [15] => Array
                        (
                            [id] => 15
                            [case] => first-letter
                            [*] => Category talk
                            [subpages] => 
                            [canonical] => Category talk
                        )

                    [102] => Array
                        (
                            [id] => 102
                            [case] => first-letter
                            [*] => Property
                            [canonical] => Property
                        )

                    [103] => Array
                        (
                            [id] => 103
                            [case] => first-letter
                            [*] => Property talk
                            [subpages] => 
                            [canonical] => Property talk
                        )

                    [104] => Array
                        (
                            [id] => 104
                            [case] => first-letter
                            [*] => Type
                            [canonical] => Type
                        )

                    [105] => Array
                        (
                            [id] => 105
                            [case] => first-letter
                            [*] => Type talk
                            [subpages] => 
                            [canonical] => Type talk
                        )

                    [108] => Array
                        (
                            [id] => 108
                            [case] => first-letter
                            [*] => Concept
                            [canonical] => Concept
                        )

                    [109] => Array
                        (
                            [id] => 109
                            [case] => first-letter
                            [*] => Concept talk
                            [subpages] => 
                            [canonical] => Concept talk
                        )

                    [5000] => Array
                        (
                            [id] => 5000
                            [case] => first-letter
                            [*] => Objects
                            [canonical] => Objects
                        )

                    [5001] => Array
                        (
                            [id] => 5001
                            [case] => first-letter
                            [*] => Matrices
                            [canonical] => Matrices
                        )

                    [5002] => Array
                        (
                            [id] => 5002
                            [case] => first-letter
                            [*] => Maps
                            [canonical] => Maps
                        )

                    [5003] => Array
                        (
                            [id] => 5003
                            [case] => first-letter
                            [*] => Models
                            [canonical] => Models
                        )

                    [5004] => Array
                        (
                            [id] => 5004
                            [case] => first-letter
                            [*] => Layers
                            [canonical] => Layers
                        )

                    [5005] => Array
                        (
                            [id] => 5005
                            [case] => first-letter
                            [*] => Enterprise Standards
                            [canonical] => Enterprise Standards
                        )

                    [5006] => Array
                        (
                            [id] => 5006
                            [case] => first-letter
                            [*] => Industry Standards
                            [canonical] => Industry Standards
                        )

                    [5007] => Array
                        (
                            [id] => 5007
                            [case] => first-letter
                            [*] => Plans
                            [canonical] => Plans
                        )

                    [5008] => Array
                        (
                            [id] => 5008
                            [case] => first-letter
                            [*] => Trends
                            [canonical] => Trends
                        )

                    [5009] => Array
                        (
                            [id] => 5009
                            [case] => first-letter
                            [*] => Industry
                            [canonical] => Industry
                        )

                    [5010] => Array
                        (
                            [id] => 5010
                            [case] => first-letter
                            [*] => LEAD Reference Content
                            [canonical] => LEAD Reference Content
                        )

                    [5011] => Array
                        (
                            [id] => 5011
                            [case] => first-letter
                            [*] => Hot Topics
                            [canonical] => Hot Topics
                        )

                    [5012] => Array
                        (
                            [id] => 5012
                            [case] => first-letter
                            [*] => FLP
                            [canonical] => FLP
                        )

                    [5013] => Array
                        (
                            [id] => 5013
                            [case] => first-letter
                            [*] => ALP
                            [canonical] => ALP
                        )

                    [5999] => Array
                        (
                            [id] => 5999
                            [case] => first-letter
                            [*] => Temp
                            [canonical] => Temp
                        )

                )

        )

)