How do you differentiate the core skill training with soft skill training? which is more useful for the employees to make them professional?

A skill is the learned ability to carry out a task with pre-determined results often within a given amount of time, energy, or both. In other words the abilities that one possesses. Skills can often be divided into domain-general and domain-specific skills. For example, in the domain of work, some general skills would include time management, teamwork and leadership, selfmotivation and others, whereas domain-specific skills would be useful only for a certain job. Skill usually requires certain environmental stimuli and situations to assess the level of skill being shown and used.

Soft skills is a sociological term relating to a person's "EQ" (Emotional Intelligence Quotient), the cluster of personality traits, social graces, communication, language, personal habits, friendliness, and optimism that characterize relationships with other people.Soft skills complement hard skills (part of a person's IQ), which are the occupational requirements of a job and many other activities.

Hard skills (core skills) are any skills relating to a specific task or situation. These skills are easily quantifiable unlike Soft skills which are related to one's personality.

Booth are very useful for the employees to do his job professionally why?

As very well explained by Binod Timsina  on his answer.

Each JD " Job Description contains  two main areas, first one is named,  KPAs " Key Performance Areas " which you need to develop and train the " Core Skills " to cover those areas. Otherwise you will have negligence of area of responsibilities,

second, part of the JD are the competencies " Soft skills " Behaviors" which will enables you achieve the KPA100%, therefore , you need to develop them too to ensure the employees are doing their jobs as required 

Regards

Sami.Balboul

Training Manager HR