A complete census of the blue horizontal branch (BHB) and blue straggler star (BSS) population within a 10' radius from the centre of the globular cluster NGC 288 is presented, based on images from the Ultraviolet Imaging Telescope (UVIT). The UV and UV-optical colour-magnitude diagrams (CMDs) are constructed by combining the UVIT, HST-ACS and ground data and are compared with the Bag of Stellar Tracks and Isochrones (BaSTI) isochrones generated for UVIT filters. We used stellar proper motion data from GAIA DR2 to select the cluster members. Our estimations of the temperature distribution of 110 BHB stars reveal two peaks, with the main peak at T_eff_~10300K, and with the distribution extending up to T_eff_~18000K. We identify the well-known photometric gaps, including the Grundahl jump (G-jump) in the BHB distribution, which are located between the peaks. We detect a plateau in the far-ultraviolet (FUV) magnitude for stars hotter than T_eff_~11500K (G-jump), which could be caused by atomic diffusion. We detect two extreme horizontal branch (EHB) candidates, with temperatures ranging from 29000 to 32000K. The radial distribution of 68 BSSs suggests that the bright BSSs are more centrally concentrated than the faint BSSs and the BHB stars. We find that the BSSs have a mass range of 0.86-1.25M_{sun} and an age range of 2-10Gyr, with peaks at 1M{sun}_ and 4Gyr respectively. This study showcases the importance of combining UVIT with HST, ground and GAIA data in deriving HB and BSS properties.

Cone search capability for table J/MNRAS/482/1080/table2 (List of UVIT detected possible cluster members)