> For the complete documentation index, see [llms.txt](https://zchains.gitbook.io/zchains-whitepaper/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://zchains.gitbook.io/zchains-whitepaper/architecture/modules/types.md).

# Types

### Overview

The **Types** module implements core object types, such as:

* **Address**
* **Hash**
* **Header**
* lots of helper functions

### RLP Encoding / Decoding

Unlike clients such as GETH, the ZChains doesn't use reflection for the encoding.\
\
The preference was to not use reflection because it introduces new problems, such as performance degradation, and harder scaling.

The **Types** module provides an easy-to-use interface for RLP marshaling and unmarshalling, using the FastRLP package.

Marshaling is done through the *MarshalRLPWith* and *MarshalRLPTo* methods. The analogous methods exist for unmarshalling.

By manually defining these methods, the ZChains doesn't need to use reflection. In *rlp\_marshal.go*, you can find methods for marshaling:

* **Bodies**
* **Blocks**
* **Headers**
* **Receipts**
* **Logs**
* **Transactions**