The LEN function returns the number of characters is a cell. It's very useful if you have to check the length of names, codes, references
Discover all the tricks and mistakes you can have with the IF function
The functions AND or OR are very useful if you have to create a test on more than 1 criteria. Have a look at the examples in this article
The COUNTIFS function in Excel works like a filter. It returns the number of rows you have in a worksheet based on one or more criteria.
Discover how to use the SUMIFS function in Excel to filter and sum data based on multiple criteria in your worksheets
The function XOR is a logical function to find exclusive OR. That's mean one and only one result (and not TRUE for both)
A logical test Is very important in Excel because it's the starting point for a lot of functions to create dynamic dashboards.
When a test in Excel returns TRUE or FALSE, you can convert it to 1 or 0 with 2 different techniques. Discover these techniques in this article