Question: How many times is the value 3 (B2) in this list (A:A)?

Answer:

=COUNT(SEARCH(B2,A:A)) + CTRL+ SHIFT + ENTER (matrix)

SEARCH(B2,A:A) returns the value 1 every time 3 is in the list (A:A)

COUNT(...) counts the number of times 1 is returned

SEARCH(find_text;within_text,[start_num]) returns the number of the character at which a specified character or text string is first found, reading left to right (not case-sensitive)

COUNT(value1;[value2];