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In this work a comprehensive analysis is made of the galaxy composition and dynamics of galaxy groups. An extensive investigation into the changing nature of the Schechter luminosity function (LF) as a function of group size (calculated in multiple ways) is carried out, with the finding that the least massive, numerically poorest and least luminous systems possess a markedly repressed faint end. The projected 2D shape of groups is analysed carefully, taking into account the distortions created by a range of effects, and there is strong evidence that the smallest groups possess an underlying oblate (frisbee) 3D shape, in contrast to more massive systems that display significantly prolate (rugby ball) distributions. The radial profiles of groups are used to identify the key regions in which the group environment strongly influences galaxy morphology, with convincing evidence that the central scale-radius determines the LF of the full range of group scales.

I have investigated the properties of the large scale structure of the nearby Universe using data from the Galaxy and Mass Assembly survey (GAMA). I generated complementary halo mass estimates for all groups in the GAMA Galaxy Group Catalogue (G³C) using a modified caustic mass estimation algorithm. On average, the caustic mass estimates agree with dynamical mass estimates within a factor of 2 in 90% of groups. A volume limited sample of these groups and galaxies are used to generate the large scale structure catalogue. An adapted minimal spanning tree algorithm is used to identify and classify structures, detecting 643 filaments that measure up to 200 Mpc/h, each containing 8 groups on average. A secondary population of smaller coherent structures, dubbed `tendrils,' that link filaments together or penetrate into voids are also detected. On average, tendrils measure around 10 Mpc/h and contain 6 galaxies. The so-called line correlation function is used to prove that tendrils are real structures rather than accidental alignments. A population of isolated void galaxies are also identified. The properties of filaments and tendrils in observed and mock GAMA galaxy catalogues agree well. I go on to show that voids from other surveys that overlap with GAMA regions contain a large number of galaxies, primarily belonging to tendrils. This implies that void sizes are strongly dependent on the number density and sensitivity limits of the galaxies observed by a survey. Finally, I examine the properties of galaxies in different environments, finding that galaxies in filaments tend to be early-type, bright, spheroidal, and red whilst those in voids are typically the opposite: blue, late-type, and more faint. I show that group mass does not correlate with the brightness and morphologies of galaxies and that the primary driver of galaxy evolution is stellar mass.