Building block

Toy blocks (also building bricks, building blocks, or simply blocks) are wooden, plastic, or foam pieces of various shapes (square, cylinder, arch, triangle, etc.) and colors that are used as construction toys. Sometimes toy blocks depict letters of the alphabet.

1693: One of the first references to Alphabet Nursery Blocks was made by English philosopher John Locke, in 1693, made the statement that "dice and playthings, with letters on them to teach children the alphabet by playing" would make learning to read a more enjoyable experience.

1798: Witold Rybczynski has found that the earliest mention of building bricks for children appears in Maria and R.L. Edgeworth's Practical Education (1798). Called "rational toys," blocks were intended to teach children about gravity and physics, as well as spatial relationships that allow them to see how many different parts become a whole.

1820: The first large-scale production of blocks was in the Williamsburg area of Brooklyn by S. L. Hill, who patented "ornamenting wood" a patent related to painting or coloring a block surface prior to the embossing process and then adding another color after the embossing to have multi-colored blocks.

1837: Friedrich Fröbel invented a preschool educational institution Kindergarten. For that, he designed ten Froebel Gifts based on building blocks principles.

1850: During the mid-nineteenth century, Henry Cole (under the pseudonym of Felix Summerly) wrote a series of children’s books. Cole's A book of stories from The Home Treasury included a box of terracotta toy blocks and, in the accompanying pamphlet "Architectural Pastime.", actual blueprints.

...
Wikipedia