Is Numera like a spreadsheet?
No. Numera lets you enter expressions in a freeform way that is, for many types of problems, easier and more flexible than using a spreadsheet. Having said that, we should say that Numera is not intended to replace your spreadsheet, but rather, to enhance your set of calculation tools. There are times, for example, when you have columns with many numbers, that a spreadsheet should be used.
A column in a spreadsheet equates to an array in Numera.
Rows and Columns in a spreadsheet equate to a matrix in Numera.
A record in a database equates to an instance of a structure in Numera.