The word topology comes from the Greek τόπος which means place and λόγος, indicates study, therefore topology is the branch of mathematics dedicated to the study of those properties of geometric bodies that remain unaltered by the continuous transformations of the discipline that studies the properties of topological branches and functions that is one of the specialization related to the characteristics that geometric bodies perform that can be sustained without alterations by continuous changes, but the type of consistency or arrangement that an object presents for compare and classify other characteristics where theconnectivity, compactness, metricity or metrizability which is a metric space with a distance function.
The continuous functions of mathematics that use the word topology with two senses as the informal one that is the specific sense above and formally alludes to a certain family of subset that is a set given by the elements that have the same characteristics and are included within another set, a family that complies with rules about the point where different things come together and the intersection. This second sense can be seen developed in the article topological space, which is a mathematical structure that allows the formal definition of convergence, connectivity.
But at the topological level, a triangle is the same as a circle, which is the closed curved line where the points are always at the same distance from another point called the center and one can be transformed into the other continuously, without the need to cut or paste.