diff --git a/assets/figures/hash-functions-1.png b/assets/figures/chapter-2/2.1.hash-functions-1.png
similarity index 100%
rename from assets/figures/hash-functions-1.png
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diff --git a/assets/figures/hash-functions-2.png b/assets/figures/chapter-2/2.1.hash-functions-2.png
similarity index 100%
rename from assets/figures/hash-functions-2.png
rename to assets/figures/chapter-2/2.1.hash-functions-2.png
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similarity index 100%
rename from assets/figures/merkle-tree.png
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similarity index 100%
rename from assets/figures/ethereum-logo.png
rename to assets/figures/chapter-2/2.6.ethereum-logo.png
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similarity index 100%
rename from assets/figures/ipfs-logo.png
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diff --git a/chapters/2.theoretical-background/2.1.hash-functions.tex b/chapters/2.theoretical-background/2.1.hash-functions.tex
index 0312c2a..afa9a24 100644
--- a/chapters/2.theoretical-background/2.1.hash-functions.tex
+++ b/chapters/2.theoretical-background/2.1.hash-functions.tex
@@ -4,7 +4,7 @@
 
 \begin{figure}[H]
 	\centering
-	\includegraphics[width=15cm]{assets/figures/hash-functions-1.png}
+	\includegraphics[width=15cm]{assets/figures/chapter-2/2.1.hash-functions-1.png}
 	\caption{Λειτουργία συνάρτησης κατακερματισμού}
 \end{figure}
 
@@ -19,7 +19,7 @@
 
 \begin{figure}[H]
 	\centering
-	\includegraphics[width=15cm]{assets/figures/hash-functions-2.png}
+	\includegraphics[width=15cm]{assets/figures/chapter-2/2.1.hash-functions-2.png}
 	\caption{Παράδειγμα λειτουργίας συνάρτησης κατακερματισμού}
 \end{figure}
 
diff --git a/chapters/2.theoretical-background/2.2.asymmetric-cryptography.tex b/chapters/2.theoretical-background/2.2.asymmetric-cryptography.tex
index a1a90d1..96fecd6 100644
--- a/chapters/2.theoretical-background/2.2.asymmetric-cryptography.tex
+++ b/chapters/2.theoretical-background/2.2.asymmetric-cryptography.tex
@@ -11,7 +11,7 @@
 
 \begin{figure}[H]
 	\centering
-	\includegraphics[width=15cm]{assets/figures/asymmetric-key-generation.png}
+	\includegraphics[width=15cm]{assets/figures/chapter-2/2.2.asymmetric-key-generation.png}
 	\caption{Παραγωγή ασύμμετρου ζεύγους κλειδιών}
 \end{figure}
 
@@ -30,7 +30,7 @@
 
 \begin{figure}[H]
 	\centering
-	\includegraphics[width=15cm]{assets/figures/asymmetric-end-to-end-communication.png}
+	\includegraphics[width=15cm]{assets/figures/chapter-2/2.2.asymmetric-end-to-end-communication.png}
 	\caption{Κρυπτογράφηση απ' άκρη σ' άκρη}
 \end{figure}
 
diff --git a/chapters/2.theoretical-background/2.3.merkle-trees.tex b/chapters/2.theoretical-background/2.3.merkle-trees.tex
index c4b1a6a..383c766 100644
--- a/chapters/2.theoretical-background/2.3.merkle-trees.tex
+++ b/chapters/2.theoretical-background/2.3.merkle-trees.tex
@@ -6,7 +6,7 @@
 
 \begin{figure}[H]
 	\centering
-	\includegraphics[width=15cm]{assets/figures/merkle-tree.png}
+	\includegraphics[width=15cm]{assets/figures/chapter-2/2.3.merkle-tree.png}
 	\caption{Παράδειγμα δυαδικού δένδρου Merkle}
 \end{figure}
 
diff --git a/chapters/2.theoretical-background/2.6.ethereum.tex b/chapters/2.theoretical-background/2.6.ethereum.tex
index 53914a6..2c29d50 100644
--- a/chapters/2.theoretical-background/2.6.ethereum.tex
+++ b/chapters/2.theoretical-background/2.6.ethereum.tex
@@ -2,7 +2,7 @@
 
 \begin{figure}[H]
 	\centering
-	\includegraphics[width=2cm]{assets/figures/ethereum-logo.png}
+	\includegraphics[width=2cm]{assets/figures/chapter-2/2.6.ethereum-logo.png}
 	\caption{Ethereum logo}
 \end{figure}
 
diff --git a/chapters/2.theoretical-background/2.7.ipfs.tex b/chapters/2.theoretical-background/2.7.ipfs.tex
index 37edab2..7408768 100644
--- a/chapters/2.theoretical-background/2.7.ipfs.tex
+++ b/chapters/2.theoretical-background/2.7.ipfs.tex
@@ -1,8 +1,8 @@
-\section{IPFS}
+\section{IPFS} \label{section:2-7-ipfs}
 
 \begin{figure}[H]
 	\centering
-	\includegraphics[width=2cm]{assets/figures/ipfs-logo.png}
+	\includegraphics[width=2cm]{assets/figures/chapter-2/2.7.ipfs-logo.png}
 	\caption{IPFS logo}
 \end{figure}
 
@@ -16,7 +16,7 @@
 	\item \textbf{Σύνδεση περιεχομένου μέσω κατευθυνόμενων άκυκλων γράφων (Directed Acyclic Graphs ή DAGs)}. Το IPFS αξιοποιεί DAGs (και συγκεκριμένα Merkle DAGs), μίας δομής δεδομένων της οποίας κάθε κόμβος έχει ως μοναδικό αναγνωριστικό το hash του περιεχομένου του (το CID).
 
 	\begin{enumitemcenteredfigure}
-		\includegraphics[width=15cm]{assets/figures/merkle-dag.png}
+		\includegraphics[width=15cm]{assets/figures/chapter-2/2.7.merkle-dag.png}
 		\caption{Merkle DAG\cite{2.7-merkle-dags-proto-school}}
 	\end{enumitemcenteredfigure}
 
diff --git a/thesis.pdf b/thesis.pdf
index 28d7ffb..9c37fbc 100644
Binary files a/thesis.pdf and b/thesis.pdf differ