System software is a program designed to run a computer's hardware and applications and manage its resources, such as its memory, processors, and devices. It also provides a platform for running application software, and system software is typically bundled with a computer's operating system.

Mail merge is a feature in Microsoft Word that allows you to create personalized documents, such as letters, envelopes, or labels, by combining a main document (containing generic content) with a data source (such as an Excel spreadsheet or a database) that contains specific information for individual recipients. This feature is commonly used for creating mass mailings or personalized communication materials.

An array is used to store values in memory. Arrays allow you to store multiple values of the same data type under a single variable name, making it easier to manage and manipulate data in programming. Arrays are commonly used in various programming languages for tasks such as storing collections of data, performing calculations on large sets of values, and iterating through elements to process them. Arrays are not used for deleting values in memory or for output; their primary purpose is to store and organize data.

In Excel 2003, the number of rows is 65,536. Each worksheet in Excel 2003 consists of 65,536 rows and 256 columns.