With the development of networks and information technology, cooperation among various applications is becoming more prevalant, and data interoperability is becoming increasingly important. Due to the autonomy and heterogeneity of data sources, the goal to achieve data sharing and schema matching has become a fundamental task of data-intensive distributed applications, a hot research issue in recent years. This paper surveys the status quo of schema matching, the basic technologies and classifications of schema matching, analysis and comparisons of some typical schema matching systems, and issues that still need to be addressed.