Does Linux not distinguish between processes and threads?

As far as I know in Linux kernel, - the structure task_struct represents threads i.e. light weight processes, but not processes. - processes are not represented by any structure, but by groups of threads sharing the same thread group id. So is the following from *Operating System Concepts* correct? > Linux also provides the ability to create threads using the clone() system call. However, **Linux does not distinguish between processes and threads**. In fact, **Linux uses the term task —rather than process or thread— when referring to a flow of control within a program.** What does it mean? Thanks. Related https://unix.stackexchange.com/questions/434092/how-does-linux-tell-threads-apart-from-child-processes