Disposable contacts were first introduced in 1987. Since then they have become one of the most popular options for contact lense wearers. They're comfortable, safe and come in a variety of different types.
Disposables are designed to be worn and discarded either daily, weekly, bi-weekly or monthly. But it's important to keep in mind a distinction, that between the replacement schedule and the wear schedule. Some are designed to be worn daily and discarded daily. But some that are labeled dailies are removed daily, cleaned and stored, then reused up to their intended lifetime. That lifetime can be one week, two weeks, or even as long as a month. Make sure you note which is which when you choose your lenses.
The more often you change your prescription contact lenses the lower the odds of health problems. Even the best of contacts reduce the amount of oxygen that gets to the surface of the cornea. That ups the chances of infection. Longer wear cycles also increase the odds of corneal abrasion, conjunctivitis and other eye health issues.
However, changing lenses more frequently can increase the odds of introducing other kinds of health problems. For example, some preservative solutions can cause an allergic reaction to some contact lens users. Wearing a pair of disposables continuously for a week, then simply throwing them away, eliminates that possibility. They come packaged in a sterile solution, so they never need to be cleaned unless they're removed and re-inserted.