Normally, a trainee is an official employee of the firm who undergoes training for the job he/she was originally hired for. Typically, a number of firms keep the training period of 3-6 months during which the person gets evaluated, after which an official decision to hire on a permanent basis is made. It is often used as an insurance measure by companies.
An intern is usually understood as a temporary position, often unpaid (but definitely not required). Usually, an intern is a student in the field who is looking for experience before seeking a job. An internship is typically for a specific short period of time (say, 4 weeks or 8 weeks).
Understanding "Trainee QA" and Stipend
Now, coming to your main query... by the term "Trainee QA," it implies you are an employee. But when it comes to the salary part and it is saying stipend, they might be going to appoint you as an apprentice. In the case of an apprentice, the stipend for the 1st year is 70% of the minimum wages of semi-skilled workers, 2nd year 80%, and the third year 90%.
First, check what stipend they are offering. If it is above the minimum wages of the state, then no need to worry; they will be treating you as an employee, and the term stipend may be used in their company for the time you will be undergoing training. Otherwise, they might have issued an apprentice letter. Apprenticeship is contractual in nature.
Hope this will be helpful.
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