My Blocks is one of the ten categories of default Scratch blocks. It holds procedures for the selected sprite. They are color-coded pink. Before any blocks are created, it is empty, except for a “Make a Block” button.
Clicking Make a Block brings up a dialogue allowing the user to make a procedure. Once OK is pressed, the new block appears in the palette and an empty definition appears in the code area.
When the procedure runs, Scratch will run the blocks below the corresponding Define block.