Why Arrays?

• Store lists of data (grades, sensor readings).
• Form the base for matrices, strings, vectors.
• Efficient: direct access via index.
• Easily processed using loops.

Accessing elements!!

Historical Perspective

Early memory (1950s–70s) used Magnetic Core Memory: tiny rings storing bits in a physical grid.

Its [row][col] access directly inspired array indexing.

Accessing arr[5] in a 5-element array...

Undefined behavior: your new superpower.

Summary

• Arrays store fixed-size collections.
• Zero-based indexing: arr[0] is first.
• Loops are natural with arrays.
• Beware out-of-bounds errors.
• Prefer `std::vector` in modern C++.