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Choosing a proper data type is the first step in developing an efficient software or hardware code. 
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These data types define the way that the corresponding values should be saved temporarily in registers 
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or permanently in external memories. 
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This section explains the data type options in HLS their related optimisation and development techniques.
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Software programming languages usually provide a set of common data types as their built-in components. 
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For example, C++ language built-in data types include bool, char, int, float double, each of which 
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can also have a modifier such as signed, unsigned, short and long. 
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The software languages also provide user-defined data types and complex data type via, struct and enumeration language 
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statements.
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As you may realize from this slide, the size of software data types are on 8-bit boundaries. 
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A proper data type has a vital role in describing a hardware circuit in HLS. C-based built-in data
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types are all on 8-bit 
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boundaries such as 8, 16, 32, and 64 bits. Hardware descriptions can use these data types to define
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their signals and ports. 
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However, most hardware circuits use arbitrary bit-width signals. 
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Therefore, introducing these bit-accurate data types in HLS is essential. 
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For example, a 23-bit data type. 
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Notice that, the built-in C-data types, used in a hardware description, may be optimised by the HLS synthesis
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tools to the exact bit-with required in the final hardware; 
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however, this is not the case in all designs.
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This section, which mainly explains the arbitrary-precision integer data types in HLS, consists 
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of 11 lectures.
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The current lecture introduces the section and talks about its structure.
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The next lecture will explain how HLS supports native C/C++ data types. Synthesising a specific 
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data type to the corresponding hardware would be the subject of the third lecture. 
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The fourth lecture will introduce the bit-accurate (or arbitrary-precision) data types in Vivado-HLS
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and how to declare variables of those types.
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The arbitrary-precision data type variable initialisation would be the topic of the fifth lecture. The sixth 
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lecture will explain the arbitrary-precision variable assignment. 
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How to print the value of an arbitrary-precision variable on the screen would be the primary concern
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of lecture seven.
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Lecture eight will review the Vivado-HLS features for arbitrary-precision variable bit-level manipulations.
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Bit-wise operators would be the topic of the ninth lecture.
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Lecture 10 will have a look at the shift and rotate operations in Vivado-HLS.
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Finally, the last lecture will give you a couple of problems to exercise all the concepts and techniques 
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explained throughout this section.