Ultrashort laser pulses are powerful and important tools for scientific researches in many areas in that they allow studying ultrafast dynamics in materials with extreme time resolution. Different experiments across different research fields ask for laser pulses with very different characteristics. Ultrafast laser pulse shaping, where the amplitude, phase or polarization of laser pulses are modulated to fulfill various requirements of different experiments, is widely used. On the other hand, the pure quest of the technology development and the desires for studying even faster dynamics in materials jointly motivate the development of ultrafast laser technology. The record of the shortest pulse duration was continuously renewed. Eventually, ultrafast lasers step into the few cycle regime thanks to the introduction of Ti:Sapphire lasers. When the pulse duration approaches the oscillation period of the laser carrier wave, the differences between few cycle pulses and longer pulses emerge. One of the most notable differences is that even for two few cycle pulses with identical envelopes, the electric fields underneath can be utterly different. Hence, full control over few cycle pulses requires direct control over the electric field, which implies the technological leap from laser pulse shaping to sub-cycle laser field shaping. Sub-cycle laser field shaping technology not only enables full control over laser pulses, but also makes possible direct manipulation of strong-field physics process via tailored optical waveforms, which fundamentally enhances the toolbox for controlling light and matter interaction.Preliminary laser field shaping can be achieved via the Carrier Envelope Phase (CEP) of laser pulses, which is sufficient to significantly affect the electric field and alter the outcomes of light and matter interactions. Therefore, CEP stabilization is crucial for laser field shaping. Currently, CEP locking methods can be categorized into active stabilization and passive stabilization. Active CEP stabilization requires feedback loops which lock the CEP mostly by tuning the inter-cavity group velocity dispersion. In contrast, the passive CEP stabilization exploits the phase relation between different beams in nonlinear optics process, where the idler beam of OPA/DFG is naturally CEP stabilized if the signal beam and the pump beam shares identical CEP fluctuation. Additionally, controlling the spectral phase precisely further enhances the shaping capability that the electric field can be shaped to deviate notably from sinusoidal oscillation. Complete characterization of such few-cycle/single-cycle pulses is indispensable for utilizing them in experiments. Typical ultrashort pulse characterization methods measure the pulse envelopes but the exact shape of the electric fields. New methods which measure the electric field have to be developed. The field-sensitive methods are usually based on high harmonic generation, either by exploiting the process itself or by employing the XUV radiation from HHG.Laser field shaping targets extending the capability of direct electric field control in radio frequency to optical frequency. Customizing optical waveforms builds on the generation of extremely broadband spectrum and precise control of the spectral phase. Since laser pulses with broad bandwidth correspond to pulses which are temporally compressible to very short duration, sub-cycle laser field shaping and sub-cycle laser pulse generation share common technological ground. However, generating spectrum experimentally with bandwidth supporting sub-cycle laser pulses with a single light source is, if not impossible, extremely difficult. On the other hand, coherent combination, or synthesis, of several few-cycle pulses of different colors is the enabling technology for extremely broadband spectrum and intense sub-cycle laser pulses. Different approaches have been proposed along the development of optical waveform synthesis. The optical waveform synthesizer based on noble gas filled hollow-core fibers is one of the most successful attempts, which leads to fruitful results. However, the HCF approach has its own limits which are, e.g. the pulse energy and the bandwidth. To overcome such limits, OP(CP)As are introduced for the waveform synthesis. After conceptual demonstration with small OPAs, the signal beam, the idler beam and even the pump beam of more powerful OP(CP)As are employed for coherent synthesis, which takes advantage of the fact that the beams are inherently synchronized. The full potential of a parametric waveform synthesizer is however yet to explore. Hence, a waveform synthesizer consists of several different OP(CP)As was built, which outputs millijoule level sub-cycle pulses and the waveform can be varied by tuning the synthesis parameters. With the intense sub-cycle pulses, isolated attosecond pulses are directly generated without the assistance of additional gating methods. Moreover, tunable isolated attosecond pulses are conveniently delivered via varying the synthesis parameters. In the meantime, simulations are performed to illustrate the shaping of the generated attosecond pulses by tailored waveforms.