JavaScript's hoisting and Temporal Dead Zone (TDZ) are often misunderstood, causing errors like 'ReferenceError: Cannot access 'myVariable' before initialization.' This occurs because var, let, and const behave differently during the compilation phase. Var is initialized to undefined and can be accessed anywhere in its scope, while let and const remain in the TDZ until their declaration, preventing access before initialization.

The TDZ is a temporal concept, meaning a variable is in a 'dead zone' from the start of the block until its declaration. This explains why let and const can't be accessed before being defined, unlike var. Understanding this distinction is crucial for avoiding common JavaScript bugs and writing robust code.

In practice, this knowledge is especially relevant in modern JavaScript development, including frameworks like React. Developers must be careful with useState and event handlers to avoid TDZ-related issues. By preferring const and let over var, and understanding the TDZ, developers can write cleaner, more predictable code.