The LENGTH function in Excel is used to find the number of characters in a text string. It can be used to count the length of a single cell or a range of cells.

The UPPER function is used to convert all the characters in a text string to uppercase. It can be used to convert a single cell or a range of cells to uppercase.

The LOWER function is used to convert all the characters in a text string to lowercase. It can be used to convert a single cell or a range of cells to lowercase.

The PROPER function is used to capitalize the first letter of each word in a text string. It can be used to capitalize the first letter of each word in a single cell or a range of cells.

The CONCATENATE function is used to combine multiple text strings into one. It can be used to combine the contents of multiple cells or ranges of cells into a single cell.

The COUNT function is used to count the number of cells in a range that contain numbers. It can be used to count the number of cells in a single column or a range of columns that contain numbers.