In 1949 Lego began producing the now famous interlocking bricks, calling them "Automatic Binding Bricks" The bricks, were a development of traditional stackable wooden blocks that locked together by means of several round studs on top and a hollow rectangular bottom. The blocks snapped together, but not so tightly that they required extraordinary effort to be separated. The bricks however, still had some problems from a technical standpoint requiring the right material and design needing to be found. In 1958, the modern brick design was developed and was patented on 28 January that year. Bricks from that time are still compatible with today's current bricks.
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