VLOOKUP will work but I would always suggest using MATCH instead, it just seems cleaner to me, and works on ranges of more than one column.
Similar principle as other example:
So MATCH looks for your value (eg A1) in some other range (which can be 1 or more than 1 row or column, ie any size or shape you like) eg C1:E25, checks for an exact match (0). This returns a value if it is found, or #N/A if not, so ISNA picks up the ones not found, and NOT reverses that so that a result of "True" means "is in the range" and "False" means "is not found"
Alternative would be to simply use COUNTIF to count how many times an item occurs in the other range, and check if that is > 0
Returns True if A1 is found in the range, False if not (don't be tempted to stick an IF round this where it is not needed, this is already a conditional formula).
Again, this supports ranges of more then one row and column if you need it to.
Don't forget to put your $ in your formulas before you copy these from cell to cell, I have left them out of the examples for readability.