EXEC sp_executesql, EXECUTE()
EXECUTE (or EXEC) vs sp_executesql
EXECUTE:
EXECUTE executes a command string or character string WITHIN a TSQL batch, or one of the following MODULES: system stored procedure, user-defined stored procedure, scalar-valued user-defined function, or extended stored procedure. The TSQL query can be a direct string or a variable of char, varchar, nchar, or nvarchar DATA type.
sp_executesql:
sp_executesql executes a TSQL statement or batch that can be reused many times, or one that has been built dynamically. The TSQL statement or batch can contain EMBEDDED parameters. The SQL query is a Unicode string or a Unicode variable that contains a Transact-SQL statement or batch. Here the variable datatype is restricted to Unicode nchar or nvarchar only. If a Unicode constant (SQL string) is used then the it must be PREFIXED with N.

EXEC sp_executesql, EXECUTE()
EXECUTE (or EXEC) vs sp_executesql
EXECUTE:
EXECUTE executes a command string or character string within a TSQL batch, or one of the following modules: system stored procedure, user-defined stored procedure, scalar-valued user-defined function, or extended stored procedure. The TSQL query can be a direct string or a variable of char, varchar, nchar, or nvarchar data type.
sp_executesql:
sp_executesql executes a TSQL statement or batch that can be reused many times, or one that has been built dynamically. The TSQL statement or batch can contain embedded parameters. The SQL query is a Unicode string or a Unicode variable that contains a Transact-SQL statement or batch. Here the variable datatype is restricted to Unicode nchar or nvarchar only. If a Unicode constant (SQL string) is used then the it must be prefixed with N.