ABSTRACT Whole Market including IT is growing very fast and with technological developments there is a high pace of diversification. The main cause of these changes is technology and a high rate of trading. Through this work I will explore the following aspects of this area: ● Provide a brief overview of what is meant by ‘market microstructure and high-frequency trading’. ● Discuss the growth in high-frequency trading. ● Determine the advantages and disadvantages of high-frequency trading. ● Discuss some of the gaps such as spaces and problems that have arisen due to COVID-19 in relation to microstructure research issues in the high-frequency world. ● Examine current issues regarding market microstructure and high-frequency trading. ● Analyse three influential themes in market microstructure and high-frequency trading/data. ● Provide an overview of regulations, giving practical examples with reference to the topic. ● Conclude the research.