Hey, welcome on board! Today's exciting journey explores multidimensional arrays in Kotlin, which are much like a chessboard in the world of programming. Our aim is to empower you to create, access, and modify these versatile arrays. So buckle up and let's get started!

Imagine a multidimensional array as an array of arrays. It operates like a chessboard; each square, which can be identified by its row and column coordinates, represents a specific value or chess piece. Note that this 2D visualization doesn't limit us. Kotlin allows us to create arrays with 3, 4, or even more dimensions, naturally extending this concept.

Kotlin provides the arrayOf() function for declaring multidimensional arrays. Here's how it works:

Kotlin
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1fun main() {
2    val chessboard = arrayOf(   // Start of the outer array
3        arrayOf("R", "N", "B", "Q", "K", "B", "N", "R"),   // Each inner array represents a row on the chessboard
4        arrayOf("P", "P", "P", "P", "P", "P", "P", "P"),
5        arrayOf("", "", "", "", "", "", "", ""),
6        // ...
7    )   // End of the outer array
8
9    // Access and print first two rows of the chessboard
10    println("Row 1: ${chessboard[0].joinToString()}")  // Outputs: Row 1: R, N, B, Q, K, B, N, R
11    println("Row 2: ${chessboard[1].joinToString()}")  // Outputs: Row 2: P, P, P, P, P, P, P, P
12}

In our chessboard array abstraction, each row represents an inner array, the elements of which we can access using two indices.

Let's use our chessboard analogy to retrieve a piece from a particular location:

Kotlin
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1fun main() {
2    val chessboard = arrayOf( 
3        arrayOf("R", "N", "B", "Q", "K", "B", "N", "R"),
4        arrayOf("P", "P", "P", "P", "P", "P", "P", "P"),
5        arrayOf("", "", "", "", "", "", "", ""),
6        // ...
7    )
8
9    val piece = chessboard[0][2]   // Access 3rd piece at the first row
10    println(piece)   // Outputs: B
11}

In the above example, piece holds "B" (representing a bishop in chess) at coordinates (0, 2) because, like most languages, Kotlin uses zero-indexed arrays.

Kotlin's mutable arrays allow for changes to elements, demonstrated as follows:

Kotlin
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1fun main() {
2    val chessboard = arrayOf(
3        arrayOf("R", "N", "B", "Q", "K", "B", "N", "R"),
4        arrayOf("P", "P", "P", "P", "P", "P", "P", "P"),
5        arrayOf("", "", "", "", "", "", "", ""),
6        // ...
7    )
8
9    chessboard[1][4] = ""  // Make the initial spot of a pawn empty
10    chessboard[0][4] = "P"  // Move pawn one square backwards
11
12    println("Row 2: ${chessboard[1].joinToString()}")  // Outputs: Row 2: P, P, P, P, , P, P, P
13    println("Row 1: ${chessboard[0].joinToString()}")  // Outputs: Row 1: R, N, B, Q, P, B, N, R
14}

While in Kotlin, the size of an existing array can't be changed, the above code showcases a simple chess pawn's movement by modifying the respective array elements.

Kudos to you on your first encounter with multidimensional arrays in Kotlin! We've understood their structure, created a chessboard analogy of an array, accessed a chess piece, and made a chess move. Essentially, we've learned how to create, access, and modify multidimensional arrays. Are you ready for some practice exercises to solidify these newly learned concepts? Let's dive in! Happy coding!