This thesis investigates the psychological impact of colours in web design. With an approach that relies on psychology and theory of colours and web design, the influence of design itself on the emotions, perception and behaviour of users in web environments is explored. The analysis begins with an examination of human senses, and continues with the psychological impact of colours, as well as other visual elements of web design, on the very perception and engagement of users. Colours and elements of web design are also presented theoretically. One of the main focuses of the work is the understanding of user behaviour patterns, the decision-making process as well as the dynamics of interaction within the web framework. By summarizing the results of existing research, practical insights and strategies for enabling effective user-oriented web experiences are determined. The conclusions emphasize the importance of considering the psychological aspects of design in shaping user perceptions and behaviour on web pages. Ultimately, this work contributes to a deeper understanding of the connection between psychology and design in web environments. By summarizing existing research and reviewing practical insights, significant guidelines are offered for designers and developers who aim to provide visually appealing experiences in web design.