Neutron stars are extremely dense objects, with masses typically ranging from 1.1 to 2.0 solar masses and radii between 9.9 and 11.2 kilometers. Recent advancements in observational techniques and computational models have significantly improved our understanding of neutron star properties. These include precise mass measurements of over 35 neutron stars, with some reaching up to 2.0 solar masses, and more accurate radius measurements, narrowing uncertainties due to better understanding of systematic errors. These findings have important implications for the equation of state of dense matter, which describes the relationship between pressure and density in neutron star interiors. The combination of these measurements, along with improved laboratory constraints on dense matter properties, has provided strong constraints on the behavior of cold, ultradense matter at densities much higher than that of atomic nuclei. Neutron star mass measurements have been primarily achieved through timing observations of binary pulsars, particularly recycled pulsars. These systems allow for precise determination of orbital parameters, which in turn provide constraints on the masses of the neutron stars. The double neutron star systems (DNSs) and millisecond pulsar-white dwarf (MSP-WD) systems are especially important for mass measurements. The most massive neutron star discovered so far has a mass of 2.01 solar masses, providing critical insights into the equation of state of neutron star matter. Radius measurements of neutron stars have also advanced significantly, with X-ray observations of low-mass X-ray binaries (LMXBs) in quiescence and during X-ray bursts providing key data. These observations, combined with detailed modeling of neutron star atmospheres, have allowed for more accurate determination of neutron star radii. The radii of neutron stars are typically between 9.9 and 11.2 kilometers, with uncertainties reduced due to improved understanding of systematic errors. The mass distribution of neutron stars is now known to be broader than previously thought, with some pulsars in the 1.9–2.0 solar mass range. This has important implications for the equation of state of dense matter, as it provides constraints on the behavior of matter at densities much higher than that of atomic nuclei. These findings have significant implications for our understanding of the composition and properties of cold nuclear matter, a major unsolved problem in modern physics. The combination of mass and radius measurements, along with improved laboratory constraints on dense matter properties, has provided strong constraints on the behavior of cold, ultradense matter at densities much higher than that of atomic nuclei.Neutron stars are extremely dense objects, with masses typically ranging from 1.1 to 2.0 solar masses and radii between 9.9 and 11.2 kilometers. Recent advancements in observational techniques and computational models have significantly improved our understanding of neutron star properties. These include precise mass measurements of over 35 neutron stars, with some reaching up to 2.0 solar masses, and more accurate radius measurements, narrowing uncertainties due to better understanding of systematic errors. These findings have important implications for the equation of state of dense matter, which describes the relationship between pressure and density in neutron star interiors. The combination of these measurements, along with improved laboratory constraints on dense matter properties, has provided strong constraints on the behavior of cold, ultradense matter at densities much higher than that of atomic nuclei. Neutron star mass measurements have been primarily achieved through timing observations of binary pulsars, particularly recycled pulsars. These systems allow for precise determination of orbital parameters, which in turn provide constraints on the masses of the neutron stars. The double neutron star systems (DNSs) and millisecond pulsar-white dwarf (MSP-WD) systems are especially important for mass measurements. The most massive neutron star discovered so far has a mass of 2.01 solar masses, providing critical insights into the equation of state of neutron star matter. Radius measurements of neutron stars have also advanced significantly, with X-ray observations of low-mass X-ray binaries (LMXBs) in quiescence and during X-ray bursts providing key data. These observations, combined with detailed modeling of neutron star atmospheres, have allowed for more accurate determination of neutron star radii. The radii of neutron stars are typically between 9.9 and 11.2 kilometers, with uncertainties reduced due to improved understanding of systematic errors. The mass distribution of neutron stars is now known to be broader than previously thought, with some pulsars in the 1.9–2.0 solar mass range. This has important implications for the equation of state of dense matter, as it provides constraints on the behavior of matter at densities much higher than that of atomic nuclei. These findings have significant implications for our understanding of the composition and properties of cold nuclear matter, a major unsolved problem in modern physics. The combination of mass and radius measurements, along with improved laboratory constraints on dense matter properties, has provided strong constraints on the behavior of cold, ultradense matter at densities much higher than that of atomic nuclei.