I come in different shapes and sizes. Parts of me are curved, other parts are straight. You can put me anywhere you like, but there's only one right place for me. What am I?

The object described by these clues is a jigsaw puzzle piece. It perfectly fits the description because each piece is uniquely shaped; some are tiny, others larger, contributing to the "different shapes and sizes" aspect. The edges of these pieces are a mix of "curved" protrusions, often called tabs or outies, and indentations, known as blanks or innies, alongside "straight" edges typically found on the perimeter pieces of a puzzle. While a piece might superficially appear to fit in several spots during assembly, there is ultimately "only one right place" where its image, color, and interlocking shape align perfectly with its neighbors (Review) to complete the overall picture.

The concept of the jigsaw puzzle dates back to the 18th century. John Spilsbury, a London cartographer and engraver, is widely credited with commercializing the first jigsaw puzzle around 1760. His initial creations were far from today's scenic landscapes; they were "dissected maps," specifically designed as educational tools. Spilsbury would mount maps onto wooden boards and then cut them along the national boundaries, allowing students to reassemble the countries and learn geography in an engaging, hands-on way.

These early puzzles were crafted from wood and were quite expensive, making them a luxury item. Over time, advancements in manufacturing led to cardboard puzzles becoming more common and affordable in the early 20th century. The name "jigsaw" itself became associated with these puzzles around 1880, referring to the fretsaws or scroll saws used to cut the intricate, interlocking shapes, though the term "jigsaw puzzle" became common around 1906. Their popularity soared, especially during the Great (Review) Depression in the 1930s, as they offered an inexpensive and enduring form of entertainment for families.