Ted Lewis (born 18 October 1969 in Bellingham, Massachusetts) is an American voice actor who does work for 4kids Entertainment, Central Park Media, TAJ Productions, DuArt Film and Video, and NYAV Post. Primarily, he is involved with anime dub voice work. He is also known as Ed Paul.
If you want to use the value of a cell in a formula in another cell of the spreadsheet, then you refer to this cell by means of its cell address. This cell address consists of a column indicator and a row number, e.g. cell D14 is the cell in column D, row 14.
In this case, the rule is evaluated for each of the 10 cells in B2:B11, and B2 will change to the address of the cell being evaluated each time, since B2 is relative. The formula itself uses the SEARCH function to find the position of dog in the text.