A non-competition clause or non-compete clause can be part of a contract with an employer. The clause says that, if in the future you resign or you are fired, you are not allowed to start your own business in the same field as your current employer: you are not allowed to compete with your current employer. Sometimes the clause also says that you cannot be employed by a competing business, after you resign or are fired.
Usually, there is a time limit: 6 months, or 12 months or maybe even 3 years. Sometimes, distance is specified: you cannot do this in the same city as your current employer, or within a distance of 100 or 250 kilometres.
The non-competition clause protects your current employer. When you leave, you cannot take business secrets or clients with you to a competitor.
When you really want the job, you probably have no problems with the non-competition clause in the contract. If you are dreaming of setting up your own business in the future - in the same field as your current employer - then the clause can be a real problem. You may end up having to wait for the specified number of months, or pay a sometimes hefty fine.