diff --git a/020_git-mergetool.sh b/020_git-mergetool.sh
index 33f8131..e386a59 100644
--- a/020_git-mergetool.sh
+++ b/020_git-mergetool.sh
@@ -1,3 +1,70 @@
-git config merge.tool meld
-#git config merge.tool gvimdiff3
+BIN_DIR=/usr/local/bin
+#BIN_DIR=~/bin
+
+# Available tools:
+git difftool --tool-help
+
+DIFF_TOOL=meld # graphical diff/merge tool
+MERGE_TOOL=meld
+
+ # DIFF_TOOL=vimdiff3 # terminal diff/merge tool
+ # MERGE_TOOL=vimdiff3
+
+#    $LOCAL is the file in the current branch (e.g. master).
+#    $REMOTE is the file in the branch being merged (e.g. branch_name).
+#    $MERGED is the partially merged file with the merge conflict information in it.
+#    $BASE is the shared commit ancestor of $LOCAL and $REMOTE, this is to say the file as it was when the branch containing $REMOTE was originally created.
+
+
+git config --global merge.tool ${MERGE_TOOL}
+git config --global merge.conflictstyle diff3
+#git config --global mergetool.${MERGE_TOOL}.cmd ${MERGE_TOOL} '$LOCAL $BASE $MERGED'
+
+git config --global diff.tool ${DIFF_TOOL}
+git config --global difftool.prompt false
+git config --global alias.d difftool
+#git config --global difftool.${DIFF_TOOL}.cmd ${DIFF_TOOL} '$LOCAL $REMOTE'
+
+git config merge.tool ${MERGE_TOOL}
 git config merge.conflictstyle diff3
+#git config mergetool.${MERGE_TOOL}.cmd ${MERGE_TOOL} '$LOCAL $BASE $MERGED'
+
+git config diff.tool ${DIFF_TOOL}
+git config difftool.prompt false
+git config alias.d difftool
+#git config --global difftool.${DIFF_TOOL}.cmd ${DIFF_TOOL} '$LOCAL $REMOTE'
+
+echo "Global: Active mergetool: $(git config --global merge.tool)"
+echo "Global: Merge style: $(git config --global merge.conflictstyle)"
+
+echo "Global: Active difftool: $(git config --global diff.tool)"
+echo "Global: Prompt for difftool: $(git config --global difftool.prompt)" 
+
+echo "Active mergetool: $(git config merge.tool)"
+echo "Merge style: $(git config merge.conflictstyle)"
+
+echo "Active difftool: $(git config diff.tool)"
+echo "Prompt for difftool: $(git config difftool.prompt)" 
+
+# to use an unsupported tool see below.
+#git config --global diff.external ${BIN_DIR}/git-diff-vimdiff.sh
+
+# the executable specified by GIT_EXTERNAL_DIFF will be called with a fixed set of 7 arguments:
+
+# path old-file old-hex old-mode new-file new-hex new-mode
+
+#cat > ${BIN_DIR}/git-diff-meld.sh <<'EOF'
+##!/bin/bash
+#echo $*
+#meld $2 $5
+#EOF
+#
+#chmod +x ${BIN_DIR}/git-diff-meld.sh 
+#
+#cat > ${BIN_DIR}/git-diff-vimdiff.sh <<'EOF'
+##!/bin/bash
+#echo $*
+#vimdiff $2 $5
+#EOF
+#
+#chmod +x ${BIN_DIR}/git-diff-vimdiff.sh