diff --git a/.DS_Store b/.DS_Store index bf5a823..8eac720 100644 Binary files a/.DS_Store and b/.DS_Store differ diff --git a/unit03_hashing/lecture/chapter03_hashing_authentication.pptx b/unit03_hashing/lecture/chapter03_hashing_authentication.pptx index 0e73728..aa9508b 100644 Binary files a/unit03_hashing/lecture/chapter03_hashing_authentication.pptx and b/unit03_hashing/lecture/chapter03_hashing_authentication.pptx differ diff --git a/unit04_public_key/.DS_Store b/unit04_public_key/.DS_Store index 77b7bd2..0532a71 100644 Binary files a/unit04_public_key/.DS_Store and b/unit04_public_key/.DS_Store differ diff --git a/unit04_public_key/lab/.DS_Store b/unit04_public_key/lab/.DS_Store new file mode 100644 index 0000000..5cad99c Binary files /dev/null and b/unit04_public_key/lab/.DS_Store differ diff --git a/unit04_public_key/lecture/chapter04_public_msc.pdf b/unit04_public_key/lecture/chapter04_public_msc.pdf index fc262a2..f0e7f23 100644 Binary files a/unit04_public_key/lecture/chapter04_public_msc.pdf and b/unit04_public_key/lecture/chapter04_public_msc.pdf differ diff --git a/unit04_public_key/lecture/chapter04_public_msc.pptx b/unit04_public_key/lecture/chapter04_public_msc.pptx index ed44bcf..5822d4e 100644 Binary files a/unit04_public_key/lecture/chapter04_public_msc.pptx and b/unit04_public_key/lecture/chapter04_public_msc.pptx differ