Hiding data technique is an effective technique for keeping data secret or making a watermarking on data such as spatial data, image, video. There are many techniques to hide data, for example, Steganography, Cryptography, or Copyright marking. The main of this paper is to review the difference between Steganography, Cryptography, or Copyright marking techniques and analyzing the Embedded, Jittering algorithm based on the Steganography program on Arcview GIS developed by William A. Hubber (Quantitative Decisions); compare the pros and con of Embedded, Jittering, and propose an Improved Jitering algorithm.