NDA / Service committment Agreement /Non-Competent Agreement
This is done by the employer to make sure that the employee will not become a competitor or will not disclose the trade secrets learnt during the employment which is of commercial value.
Generally this agreement will be renewed every year or once n two years as desired.
However once the employee resigns the company normally without breaching the agreement for a year or so, the employer has absolutely no right to interfere in his post-resignation employment or growth (Judgement by Supereme court).
On the general view such agreements will threaten them to obey the rules and go with comittment.
Regards,
Chandru