In TypeScript, we can define a variable that can have multiple types of values. In other words, TypeScript can combine one or two types of data (i.e., number, string, etc.) in a single type, a union type. Union types are a powerful way to express a variable with multiple types. Two or more data types can be combined using the pipe (’|’) symbol between the types. For example, (type1 | type2 | type3 | .. | typeN).
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