If your wall will have dirt behind it, it is considered a retaining wall. Retaining Wall Blocks are designed with lips and setbacks to give them strength to stand up to the pressure of the dirt behind them. They are only textured on the front which is the only surface to be seen.
If there is no dirt behind your wall and it can be seen from both sides, then it is considered a freestanding wall. Freestanding Wall Block has texture on both sides and does not 'setback,' or lean. These walls are typically used for defining areas such as courtyards and patios.
Which type of wall do you have?
Retaining Wall - there is dirt behind it and I can only see the front
Freestanding Wall - there is no dirt behind it & I can see it from both sides