it is a common method of website promotion. it mainly has the following advantages and disadvantages, advantages and low prices. the cost of maintaining a one-year ranking may be just bidding for less than one or two months, which is cheaper than bidding and simple management. the company does not need special personnel management. everything is maintained by the website optimization service provider. the company only needs to observe whether the ranking position is stable and the engine is universal. the advantage of website optimization is that it has no engine independence. the ranking will improve on multiple search engines, bringing more effective visitors to the website...