The paper Uday Reddy found in his answer, On Understanding Types, Data Abstraction, and Polymorphism (1985), gives the following answers:

Programming languages in which the type of every expression can be determined by static program analysis are said to be statically typed. Static typing is a useful property, but the requirement that all variables and expressions are bound to a type at compile time is sometimes too restrictive. It may be replaced by the weaker requirement that all expressions are guaranteed to be type consistent although the type itself may be statically unknown; this can be generally done by introducing some run-time type checking. Languages in which all expressions are type consistent are called strongly typed languages. If a language is strongly typed, its compiler can guarantee that the programs it accepts will execute without type errors. In general, we should strive for strong typing and adopt static typing whenever possible. Note that every statically typed language is strongly typed, but the converse is not necessarily true.

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The paper Uday Reddy found in his answer, On Understanding Types, Data Abstraction, and Polymorphism (1985), gives the following answers:

Programming languages in which the type of every expression can be determined by static program analysis are said to be statically typed. Static typing is a useful property, but the requirement that all variables and expressions are bound to a type at compile time is sometimes too restrictive. It may be replaced by the weaker requirement that all expressions are guaranteed to be type consistent although the type itself may be statically unknown; this can be generally done by introducing some run-time type checking. Languages in which all expressions are type consistent are called strongly typed languages. If a language is strongly typed, its compiler can guarantee that the programs it accepts will execute without type errors. In general, we should strive for strong typing and adopt static typing whenever possible. Note that every statically typed language is strongly typed, but the converse is not necessarily true.